Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines
The Regular Stuff: Chat, Buy, Sell, Off Topic, etc. => General Discussion - Model & Toy Steam Engines – Stirling Cycle – Flame Lickers – Small Antique Originals => Topic started by: propforward on February 24, 2020, 08:41:10 pm
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I went to Rollag and Nowthen last year. I was looking at your channel last night, and I definitely have Black Hills and Atwater on my list for this year. Next year I'd like to get to Cabin Fever. I didn't go this year just because of covid, but with a bit of luck we'll be done with that by next year.
I was at Rollag Friday and Saturday last year. I need to make it to Atwater, but it’s the same weekend as James Valley Threshers in Andover, SD…
I think it's good to mix it up a bit, go to different shows each year. But the decision making causes me conniptions!
Whoops - double post. Sorry about that.
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I think it's good to mix it up a bit, go to different shows each year. But the decision making causes me conniptions!
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I went to Rollag and Nowthen last year. I was looking at your channel last night, and I definitely have Black Hills and Atwater on my list for this year. Next year I'd like to get to Cabin Fever. I didn't go this year just because of covid, but with a bit of luck we'll be done with that by next year.
I was at Rollag Friday and Saturday last year. I need to make it to Atwater, but it’s the same weekend as James Valley Threshers in Andover, SD…
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I went to Rollag and Nowthen last year. I was looking at your channel last night, and I definitely have Black Hills and Atwater on my list for this year. Next year I'd like to get to Cabin Fever. I didn't go this year just because of covid, but with a bit of luck we'll be done with that by next year.
Loved your video of your Unimat machines - very nice indeed!
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I have subscribed to your channel as well. Given how many shows there are in Minnesota every year, are there any that you attend?
Jim in Minnesota
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Thanks all - glad you enjoyed it.
I enjoyed the full build log on this. Looks like you have a really nice shop, and well equipped.
Jim in Minnesota
Hey Jim, I'm in Minnesota as well. It has been a labor of love for quite a few years, but I'm pretty happy with how the shop has turned out, and I sure enjoy being in it. I subscribed to your channel, some great videos on there, I'll be watching them all this evening!
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Nice job!
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I enjoyed the full build log on this. Looks like you have a really nice shop, and well equipped.
Jim in Minnesota
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Real nice posting. It's really nice to be able to make things for yourself in the shop. If you make a mistake during work time you have to deal with the boss. Real nice machining. Good job.
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And - finished engine, although I still need to make a better display base.
https://www.youtube.com/watch?v=r_fkghSZOnA&t=9s
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I drilled the locking screw hole in the flywheel. Spot faced first, then center drilled, then the tap drill. I have this nice ER11 collet holder which lets me get in to tight spaces such as this, and makes the drilling and tapping a breeze. Much better concentricity than a pin vise style holder.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-djWjg9q/0/7b51b382/X2/IMG_6295%20%28Medium%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-djWjg9q/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-XFMxDkQ/0/81b6617d/X2/IMG_6296%20%28Medium%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XFMxDkQ/A)
Couldn't use a tap holder, so I just used the ER11 set up to hold the tap. Disengaged the gears and turned it by hand.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-9dgbHC5/0/622882df/X2/IMG_6297%20%28Medium%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-9dgbHC5/A)
I then spent some time doing some assembly. This is what I have so far.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-xtmvMjc/0/f1830ba2/XL/IMG_6300%20%28Medium%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xtmvMjc/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zcp2GMW/0/fedc3877/XL/IMG_6301%20%28Medium%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zcp2GMW/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-qjkdb85/0/7f125c83/XL/IMG_6302%20%28Medium%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-qjkdb85/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-k4r84Hx/0/d862a4b2/XL/IMG_7604%20%28Medium%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-k4r84Hx/A)
I got this far, and was having trouble getting the steam chest cover screws in, and also the screws for the valve rod gland. Not too surprising, since I hadn't tapped them yet. :embarassed:
Still, I was able to manually turn everything over, and there are a couple of areas that would benefit from some tweaking, so I will strip it all down and address those items, and maybe next weekend I'll be able to give it its first test on air.
I tapped the remaining holes, and reassembled today. After spending a little time setting up the timing carefully, I attached a compressed air line and the engine took off immediately without me having to touch it! You can imagine that I was quite delighted at that. Here is a little video I shot to show it running. I am pleased. It is far from perfect, but it runs quite well. It is worth going the extra distance to now strip it and paint it, and make a base of some sort for it, but otherwise I consider it complete and shall move on to another project.
It runs well at about 12 psi. 10 psi is getting on the edge, and below that it stalls.
https://youtu.be/12aUoIRIm9c
The experiment was not a dismal failure, even if not a complete success.
The valve started thus
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pnf9ZTr/0/d58b5d6f/X2/IMG_8328%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pnf9ZTr/A)
I filed the edges to be built up to get them clean, and degreased the part in acetone, then set it up on my weld table in a clamp.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-3c9trGb/0/71097d09/X2/IMG_8329%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-3c9trGb/A)
Showing the part the business end of my TIG torch. This is a 3/32 electrode, and a 1/16" would have been more appropriate.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZjxpXjL/0/7fbbdcc5/X2/IMG_8330%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZjxpXjL/A)
Anyway, as blobby as it looks I did manage to build up the edges with some silicon bronze.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-MrPkN7G/0/2a404f18/X2/IMG_8334%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-MrPkN7G/A)
After some initial machining and clean up, I ascertained that the silicon bronze was properly bonded to the part, and it actually machined well.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-kdJjmG6/0/9207afe0/X2/IMG_8470%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kdJjmG6/A)
However, I had not built up the edge quite enough, so after clean up and machining I only gained a small amount on each side. At this point I decided I had put enough time into this. Overall the concept showed signs of success, and I managed to build up the tiny part without completely melting it, so I'm pleased with that - but now I'm just going to move on with life and make a new valve.
Here it is so far:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-xTwL5JV/0/d9e28f28/X2/IMG_8468%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xTwL5JV/A)
A simple part really, I'll finish it tomorrow.
I have also been painting the engine - I degreased everything in isopropyl alcohol in a cheap ultrasonic bath, then primed with automotive primer, and let cure overnight.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-wJGJz7z/0/10f21f70/XL/IMG_8409%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wJGJz7z/A)
And then made use of my scale model spray booth to paint it, using a tin of RAF roundel blue enamel paint that I've had since about 1996 or something.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-WfrHXrQ/0/5dc39fe5/XL/IMG_8417%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-WfrHXrQ/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zpQpXnR/0/a46a8aa1/XL/IMG_8418%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zpQpXnR/A)
It's perhaps a little brighter than I intended, but overall I quite like it.
So - more progress. I have to figure out a base yet, haven't decided what to do for that.
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I had some fun today making these fiddly little fellows - oil cups. I ground a 45 degree chamfer tool which made short work of these. Not much to them really, although drilling the little through hole takes some care. Otherwise pretty simple - but being so small I am rather pleased with the result.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HpCT9dz/0/03979426/XL/IMG_7573%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HpCT9dz/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-4p32qrJ/0/dba93e75/XL/IMG_7575%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4p32qrJ/A)
The inside finish isn't the best - maybe the drill wasn't in the best shape.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zkh9nWz/0/f9062b18/XL/IMG_7574%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zkh9nWz/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-k2NVt2d/0/fef0998d/XL/IMG_7577%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-k2NVt2d/A)
Still not too shabby and they look the part well enough.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-WRj2pBp/0/861ec7a4/XL/IMG_7578%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-WRj2pBp/A)
Not many parts left now. I need to form up the eccentric connecting rod, then it's time for the flywheel, then assembly and test.
time for the flywheel. I spent a good half hour first filing off some of the sharp parting lines on the spokes and rim ID, and just generally smoothing it out and cleaning it up. My chosen approach for machining sequence was to mount it on a faceplate, but stood off from the faceplate on some aluminum spacers - 3 of them - around the rim. I set that all up on the bench, and measured the clearance between the backside of the hub and the faceplate, and machined an aluminum support block to fit snugly in there, so as to not spring the hub when making the bore. As you can see, the spokes are quite spindly.
During set up I also measured the flywheel and the gap behind the rim in multiple places, to make sure the casting was sitting fairly parallel to the faceplate. Although there is plenty of stock I don't want it mounted at an angle, resulting in a thin rim in places or something weird. Then I transferred the set up to the lathe, where I tried to center the ID of the rim and the OD of the hub by eye, using a pointer.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-W63hP5X/0/dc478c97/XL/IMG_6282%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-W63hP5X/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-cFfkxh3/0/fd957a1f/XL/IMG_6283%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-cFfkxh3/A)
The idea is to try and keep cast features concentric so that things don't look completely out of whack when operating. In the end, it turns out that the opposite sides of the casting were mis matched, and there was a flat spot on the rim, so I could only do so much to keep the as cast features running true - but I at least balanced it as best as I could.
Then I took my time to make sure that I could actually get tools in where they needed to go.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Tmdkjdv/0/14322143/XL/IMG_6287%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Tmdkjdv/A)
I wasn't planning to turn the OD of the hub - but made sure I had the option available.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-b44KrCf/0/962c737b/XL/IMG_6288%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-b44KrCf/A)
Setting up to make sure I could run the tool completely off the rim:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-KD7pG2n/0/5692d65d/XL/IMG_6289%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KD7pG2n/A)
It all worked like a charm, and went without drama. I ran the lathe in back gear at 50 rpm, so as not to risk my set up, but it was completely solid. No singing, ringing or squealing from the part during machining - it went very well indeed.
I did find a couple of casting voids in the rim. I elected not to remove them all the way.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-tsvjvZn/0/6e33992c/XL/IMG_6290%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-tsvjvZn/A)
The bore was made by drilling with 4 different sizes of drill to remove most of the material. Then I changed over to a boring tool to take out about 25 thou. My thinking here is that this gives a better chance of making the hole concentric and parallel to the axis of the rim - a drill might have wandered a bit. When there was only 0.008" left to go, I changed over to a chucking reamer to finish the hole.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-JXsnvGR/0/65e5c5b0/XL/IMG_6291%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-JXsnvGR/A)
Checking the bore along the way with gauge pins. Exceptionally versatile tools - I am so glad I purchased a set.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-QpGHj3d/0/793f2210/XL/IMG_6292%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QpGHj3d/A)
Final check after reaming - a 375 minus pin slips in, a 376 does not. Perfect!
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-vBhwNq6/0/9c165584/XL/IMG_6293%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-vBhwNq6/A)
I did not take pictures of the second side - but all that happened there was in essence the same as the first side, the only difference being that I clamped the machined surface of the rim directly to the face plate, and then trued the part up by clocking on the machined outer diameter of the rim.
Once that was complete I transferred to the mill for the locking screw feature - which is a tapped hole through the hub at 15°. For that I set up and angle plate at 15°, which was established using an angle slip gauge to the milling table.
Here I have the flywheel clamped to the angle plate at the hub. Set up is not yet complete, but I ran out of energy somewhat, and besides it's time to get supper going.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-64ZM49Q/0/ba26b0d7/XL/IMG_6294%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-64ZM49Q/A)
So tomorrow I hope to finish clamping the flywheel, then get the upright spoke as close to upright as possible. Then I'll find the center of the wheel, mill a flat in the hub, and drill and tap the screw hole. And that will be that.
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I made the 4 off 5-40 brass nuts for this engine. Not exactly thrilling stuff, but I put my new mini chuck to use, and it worked a treat. Not very complex so I'm not going to waste your time with a blow by blow account, but here they are with the mini chuck in use
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-kksCrDh/0/e12cce9c/L/IMG_6220%20%28Large%29-L.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kksCrDh/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-D5jLtKn/0/5d81dd74/L/IMG_6221%20%28Large%29-L.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-D5jLtKn/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-LxgcfTF/0/3f57e04b/L/IMG_6223%20%28Large%29-L.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-LxgcfTF/A)
That little chuck is going to be exceptionally useful over time.
Two "whoops" moments today. The first was sweeping my precious nuts off the bench onto the floor. Happily found my nuts again though.
The second had me turning the air blue.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-mJnx37t/0/ee3ca57c/L/IMG_6224%20%28Large%29-L.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-mJnx37t/A)
I was going to re make the connecting rod out of bar stock, and figured out an intricate sequence to machine it without marking out, using a rotary table to make various rounded features. I'm pretty sure that would have (or could have) worked, but on a whim I called PM Research and discovered the price of a new casting was six dollars. With brass bar being close to the value of gold, or so it seems, I bought the replacement part. I was pleased to discover that PM Research have been so busy they have had to add more staff just to deal with orders. The nice lady I spoke to was very new, and I was her first foray into supplying spare parts. In the background I heard one of the main people there assuring her that "lot's of people need to buy replacement part one offs". I suppose that reassured me a bit also.
Anyway, here is a sequence of pictures for the sake of it. Made much the same as the last one, although I hope to get the split line in the right place this time.
I have learned to spend a fair amount of time measuring castings and understanding the starting part, so as to think through where the stock is on the part, and understand whether the starting part is symmetrical, or how it relates to the finished part. After that I drew up a machining plan. So first step was getting the thickness of the bosses to size, which involved taking slightly more off one side over the other to try and keep the bolt bosses central.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-WT3cDfs/0/92d52944/XL/IMG_7480%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-WT3cDfs/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-LwQspVv/0/dbce9431/XL/IMG_7481%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-LwQspVv/A)
I then set up a knee (angle plate - we call them knees at work, and I quite enjoy using that term) to hold the part for drilling and tapping the bolt bosses. I aligned it by touching off on the tops and sides of each bolt boss, and tweaking it until they were evened out.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-L9V6dr3/0/61d5a833/XL/IMG_6246%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-L9V6dr3/A)
I machined off some of the gate feature - but not all of it. This is a qualifying surface - i.e. one I can use to register in later operations, knowing it is perpendicular to the axis of the part. I also cleaned the tops of the bolt bosses.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HgCF77f/0/3bd8cbd2/XL/IMG_6247%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HgCF77f/A)
Having done that, I established the center of the part by touching off on the sides in both X and Y directions. I spotted the qualified surface just in case that might be useful later on. Then drilled and tapped the bolt holes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-JWFtQv2/0/0d77bff0/XL/IMG_6248%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-JWFtQv2/A)
Then I set up an aluminum jig plate that I had used previously to hold the bed casting (sole plate?). I used this piece of aluminium because I had fly cut it previously on both sides, and I knew it was flat and parallel, and also preferred over drilling into the mill table. I suppose I could have used this in the first place and drilled the holes in the part in the same set up as milling the thicknesses. Oh well.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-xqqC22J/0/1084f4ab/XL/IMG_6249%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xqqC22J/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GHSvPhg/0/4c7a235b/XL/IMG_6250%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GHSvPhg/A)
Here I am using the qualified surface to verify squareness to the X and Y axes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-x5TzQf3/0/92f9c103/XL/IMG_6251%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-x5TzQf3/A)
I used a gauge pin to center the little end under the spindle - just done visually to get the zero point.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-gLmgH7f/0/6ef5c902/XL/IMG_6252%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-gLmgH7f/A)
After that I lightly marked the center of the little and big ends, and performed a quick measurement of the big end to be sure I was central.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-F7rvxK8/0/88a5d366/XL/IMG_6253%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-F7rvxK8/A)
After drilling and reaming the two holes, I was pleased to find that a .250 gauge pin would slide in, but a .251 gauge pin would not.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-RSRg6H5/0/952bb8d0/XL/IMG_6254%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-RSRg6H5/A)
Note: I checked the little end using the actual wrist pin as well, in case I needed to ream slightly over to fit that, but it fit perfectly. Also - the final hole size in the big end will be .375. I have a .25 hole in there right now to aid in set up for slitting the big end. After that is done, and the caps milled to size, then the end cap will be attached and the hole opened up to .375. I probably don't need the .25 hole in place, but I think it may help visually, plus I can touch off on a gauge pin inserted in it when setting up the slitting operation. This is the part I got wrong before (aside from breaking the thing being foolish later on). So - getting there. But that's all for today.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-KCgfnCX/0/c515fcad/XL/IMG_6256%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KCgfnCX/A)
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Made the other half of the valve arm linkage.
(https://photos.smugmug.com/photos/i-j9vzVM5/0/XL/i-j9vzVM5-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-j9vzVM5/A)
(https://photos.smugmug.com/photos/i-VT7qtnZ/0/XL/i-VT7qtnZ-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-VT7qtnZ/A)
Still need to radius the lobes, which I shall do on the belt sander once I have made a rod to hold on to it. On future engines I'll use a radius cutter or some other technique to properly radius the ends of these kinds of parts, for now a gentle hand applied radius will do.
Nuts!
Well, cross slide nut.
(https://photos.smugmug.com/photos/i-7TnSFVK/0/XL/i-7TnSFVK-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-7TnSFVK/A)
I also made the hex locking nut for the piston rod. No pics of that - a simple enough part.
So, family shot as it stands now, including the ghost of Engine Past - my beloved Elmer Number 14, and at least one scrap item I see.
(https://photos.smugmug.com/photos/i-KSw4L9j/0/XL/i-KSw4L9j-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KSw4L9j/A)
These are awkward little parts.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-H9Zx3Bd/0/3f12ebe8/X2/IMG_6039%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-H9Zx3Bd/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Khqq5P8/0/86b2f6cd/X2/IMG_6040%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Khqq5P8/A)
I putzed around for a while trying to come up with various half baked approaches to holding the castings, getting ever impatient, but managed to reign myself in, decided to just take whatever time was needed and make some sort of holding fixture.
The techniques I have seen for making these parts include super gluing them to aluminum bosses, and pressure turning. I don't want to use those approaches, I prefer mechanical holding, so that was my approach.
First off, cleaned the casting gates off.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-htTXMgr/0/5a2e3a36/XL/IMG_6077%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-htTXMgr/A)
Then started scratching up some ideas, based on some measurements from the actual casting. I have a bunch of 1" diameter aluminum slugs laying around, all 5/8" long. These were thrown out by a previous employer. No idea what they were for, but they do come in handy from time to time.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-xCxnt97/0/303ba93e/XL/IMG_6078%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xCxnt97/A)
The idea initially was to make essentially a holder in soft material so that I could turn the holder as well as the part. I was at first considering the pressure turning route.
Since I already had the collet chuck mounted and trued, this gave me a nice way of getting in close to the part.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-xQrQkz2/0/fcfaaa8d/XL/IMG_6079%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xQrQkz2/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-SrwRxvx/0/408e317a/XL/IMG_6080%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-SrwRxvx/A)
It was at this point that I decided to add four tapped holes for set screws to clamp the part. I wish I had decided on that first, it would have been better to tap the holes on the circumference before boring the recess.
Anyway this meant making use of the new dividing head, in order to add 4 tapped holes around the circumference. This is just a pic of the head getting trued up.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zwc2jDG/0/b20f7d0e/XL/IMG_6081%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zwc2jDG/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-PL943Rt/0/ddf2dbac/XL/IMG_6082%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-PL943Rt/A)
So the tapped holes went in wonky because of course I was drilling into half thickness material at some points. But it still worked.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-j9rRVHh/0/9228cc67/XL/IMG_6083%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-j9rRVHh/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-KjVkBjs/0/87d5bea1/XL/IMG_6084%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KjVkBjs/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-QRMxvZH/0/71bbd1d7/XL/IMG_6085%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QRMxvZH/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZkZhXMW/0/c2810370/XL/IMG_6086%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZkZhXMW/A)
After machining to size on the lathe, this left only the two screw holes for clamping the gland to the steam chest - so another advantage of this little fixture was that I could transfer the part to the dividing head chuck and maintain concentricity of the boss and through hole to the OD of the fixture.
I used a gauge pin in the collet holder to center the spindle axis to the part, then moved the table to position the gauge pin at 1/4" distance from the center, and simply rotated the dividing head, visually aligning each lobe to the pin - obviously moving the pin from one side to the other. Then clamped the dividing head, changed over to the #41 drill, and drilled the two holes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-6wQPG2t/0/6f19a6c9/XL/IMG_6088%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6wQPG2t/A)
When all was said and done, the part came out well. The one side does not look centered, but that's a result of my over clean up on one side.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-9Hvwfmb/0/5977d0f2/XL/IMG_6089%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-9Hvwfmb/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-N4gFhZQ/0/08f30224/XL/IMG_6090%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-N4gFhZQ/A)
Up close it looks a bit rough, and does need a debur - but dimensionally it is spot on and fits the steam chest perfectly. So whereas I am usually lamenting about things not going right, this time it turned out, and I'm happy with it.
I made a start on some test assembly.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-2ZN2hxn/0/24e88a7e/XL/IMG_6051%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-2ZN2hxn/A)
Very pleased to find that I can turn the crank over with my fingers, and the piston rod slides nicely in and out of the inboard head. Very, very pleased with this. Just need to stay the course now - it's finally looking kinda sorta like an engine.
I made another holding fixture for the cylinder gland. This time I got the sequence right, and drilled and tapped the set screw holes before boring / drilling. I also put them in at a slight angle (about 1°) so that when tightening on the part, they force it down into the fixture. That was the idea anyway, and it seems to have worked.
The bore was made to tightly fit the largest diameter of the gland, to help hold it concentric to the center axis.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-6Tjkn2z/0/92024791/XL/IMG_6094%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6Tjkn2z/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-D2XWzd6/0/81ce73c1/XL/IMG_6096%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-D2XWzd6/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-rwWpNsd/0/ca95efe9/XL/IMG_6097%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-rwWpNsd/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Tf385zG/0/13836087/XL/IMG_6098%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Tf385zG/A)
I did have an oops. Tool dug in - I must have tried to take too much off.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-m6NhC6V/0/ab74e6e3/XL/IMG_6100%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-m6NhC6V/A)
I t dug into the part and made it look ugly - but happily there was a fair bit of stock still to come off, so it cleaned up OK.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-N6SkmtK/0/d4be268e/XL/IMG_6101%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-N6SkmtK/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pLbLsNG/0/a019c067/XL/IMG_6102%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pLbLsNG/A)
Off to the mill - centered using a gauge pin,
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Xv8DBLX/0/f13a4200/XL/IMG_6103%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Xv8DBLX/A)
then rotated the part back and forth until a gauge pin looked even on both ears, and then drilled the holes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-kFFQ4gQ/0/f08f1741/XL/IMG_6104%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kFFQ4gQ/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Q8PnLxr/0/d60ad861/XL/IMG_6106%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Q8PnLxr/A)
Rotten finish on the front. It buffed up OK though.
I had been working on a follow rest system for supporting small diameter shafts for turning and single point threading. It was way too complicated, and a complete failure. Based on something I saw Joe Pie demonstrate on youtube, and also on a thread on this very forum, I modified the follow rest and made it much simpler, and a lot more effective.
Essentially, I am just using my lathe follow rest, but I had made a new adjusting shaft and a bracket for it. The original idea was to use a couple of very small ball bearings to support the shaft.
In the end though, it's easier to bolt a piece of material (in this case a piece of phenolic) to the bracket, and just use an end mill in the chuck to drill a hole in situ, so that the support is perfectly centered.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-j3vm58d/0/e8c48543/XL/IMG_6207%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-j3vm58d/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-97TBMpz/0/6f334cef/XL/IMG_6208%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-97TBMpz/A)
It's then very easy to position the cutting tool close to the support for whatever work you need to do.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-45hxLZ4/0/d7c8e015/XL/IMG_6209%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-45hxLZ4/A)
I used the "upside down tool" approach for single point threading, so that the cutting tool moves away from the headstock.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pv4dFr3/0/934c976a/XL/IMG_6210%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pv4dFr3/A)
And it works a treat.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-k3WCmdb/0/e98528c9/XL/IMG_6213%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-k3WCmdb/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-QBvHkP8/0/cef7227b/XL/IMG_6214%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QBvHkP8/A)
So I'm well pleased with that - no need for expensive dies for cutting small threads. Just as well, because the cheap dies are awful, I have had no luck with them at all - a waste of money. But this follow rest approach works really well.
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I took a rusty old lump of some sort of steel - no idea what alloy - I liberated it when it was thrown out at work about 12 years ago. Anyway, this became the basis for a holding jig for the crankshaft. There now follows pictures, but not much explanation. (Further research leads me to believe it is 4140 HT. Partly because of the yellow identifier colour one end, and because all the materials at that little firm came from McMaster Carr - I believe that's their identifier - could be wrong).
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GSF8cqc/0/9340b1c9/XL/IMG_6019%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GSF8cqc/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fV2TmcX/0/11b72c7a/XL/IMG_6020%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fV2TmcX/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-DZRJR7Z/0/9e1f4a01/XL/IMG_6021%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-DZRJR7Z/A)
I like my rolly-cart, which is handy for holding up drawings close at each machine, as well as essential tools. Like the engineers universal adjusting tool (coarse version).
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-9nMNdSq/0/f9885c05/X2/IMG_6022%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-9nMNdSq/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-j6PTX6K/0/b73d999e/X2/IMG_6023%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-j6PTX6K/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-J8VVPcg/0/64cfdc59/X2/IMG_6025%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-J8VVPcg/A)
To the mill - and centering with the very fun centering indicator.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-26GMCdV/0/04e6ad69/X2/IMG_6026%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-26GMCdV/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-sfRLv7G/0/1b35bf98/X2/IMG_6027%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-sfRLv7G/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-R4hKDW3/0/6922516e/X2/IMG_6028%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-R4hKDW3/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-KftdXFF/0/dc7eb3d4/X2/IMG_6029%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KftdXFF/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-xCwSfJQ/0/f4c6110e/X2/IMG_6030%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xCwSfJQ/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-55JgfMh/0/02ec09f3/X2/IMG_6031%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-55JgfMh/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GmdtjSB/0/5fc0c4a9/X2/IMG_6033%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GmdtjSB/A)
I tried it in the 3 jaw first - the design of the jig (slightly different to mine) comes from PM Research, and the idea is to use it this way to get the crank throw. It works well, I only ended up 0.003" off.
However, I never intended to use the 3 jaw (although let's face it, that would work fine), but I got it to 0.0005" in the 4 jaw.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bTsZNpK/0/c90cdf6a/X2/IMG_6035%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bTsZNpK/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-4Qk449q/0/ba082840/X2/IMG_6036%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4Qk449q/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-jhhJpD2/0/713a344b/X2/IMG_6037%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-jhhJpD2/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Sx4Qwq8/0/aaddbec3/X2/IMG_6038%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Sx4Qwq8/A)
Crankshaft finished, and made a start on the connecting rod.
(https://photos.smugmug.com/photos/i-gpQX8dB/0/XL/i-gpQX8dB-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-gpQX8dB/A)
(https://photos.smugmug.com/photos/i-kWB54fh/0/XL/i-kWB54fh-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kWB54fh/A)
(https://photos.smugmug.com/photos/i-tFvK3s5/0/XL/i-tFvK3s5-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-tFvK3s5/A)
(https://photos.smugmug.com/photos/i-4dnk7J4/0/XL/i-4dnk7J4-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4dnk7J4/A)
(https://photos.smugmug.com/photos/i-5D5CPdr/0/XL/i-5D5CPdr-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-5D5CPdr/A)
(https://photos.smugmug.com/photos/i-xTGn9sN/0/XL/i-xTGn9sN-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xTGn9sN/A)
(https://photos.smugmug.com/photos/i-2vLhp98/0/XL/i-2vLhp98-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-2vLhp98/A)
(https://photos.smugmug.com/photos/i-rmVhDws/0/XL/i-rmVhDws-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-rmVhDws/A)
(https://photos.smugmug.com/photos/i-XL96cSd/0/XL/i-XL96cSd-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XL96cSd/A)
(https://photos.smugmug.com/photos/i-wDhwT4B/0/XL/i-wDhwT4B-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wDhwT4B/A)
(https://photos.smugmug.com/photos/i-hXzDd2k/0/XL/i-hXzDd2k-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-hXzDd2k/A)
Holes in big end drilled.
(https://photos.smugmug.com/photos/i-4mhZR2H/0/X2/i-4mhZR2H-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4mhZR2H/A)
Note that I left the casting gate in place, and also milled it flat as a reference surface.
Then re-positioned to get the little end hole drilled. I used that reference surface as an aid to squaring up the part. I used a pin gauge of the same diameter as the little end OD to do a visual centering alignment.
(https://photos.smugmug.com/photos/i-7ZW6Hfr/0/XL/i-7ZW6Hfr-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-7ZW6Hfr/A)
Drilled and reamed for a pin.
(https://photos.smugmug.com/photos/i-tNVZtvJ/0/XL/i-tNVZtvJ-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-tNVZtvJ/A)
I then went and drilled a 1/4" hole at the finished distance (3.375") from the little end. This will give me a visual aid when I saw the big end in the next step.
Now - I was sorely tempted to make a 3/8" slot, to become a 3/8" hole after slitting the big end. However - I felt that was being too cocky. I've seen it done - but the guy who did it is a highly experienced production machinist. You can see the video on youtube.
For now I'm taking the simple approach.
Pleased with this though - the holes are nicely centered.
(https://photos.smugmug.com/photos/i-6Wv2xsf/0/XL/i-6Wv2xsf-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6Wv2xsf/A)
Next step is to slit the big end, bolt it back together and finish the big end bore.
-
Well I did a little close up investigation, and re measured OD of the hub and ID of the follower, and discovered that within the measuring capability of my calipers, ID and OD are identical. Couldn't have achieved that if I'd tried for it. I can get a 2 thou feeler gauge in this gap, and freely rotate the hub.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-QFJxjQq/0/c90d070e/XL/IMG_5996%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QFJxjQq/A)
So I gave the follower a polish on the ID, and the hub a polish on the OD, and after that they go together nicely and the hub rotates freely in the follower. Sort of disappointed, but polishing those two diameters to a better finish is not a bad thing anyway I guess.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-qgnDJdM/0/44e4062d/XL/IMG_5997%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-qgnDJdM/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-jcxSTsq/0/1d4aac37/XL/IMG_5998%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-jcxSTsq/A)
The photos tend to exaggerate surface roughness, but even so I could have done better on the face of the hub with the offset boss on it. Should have done a skim after making the offset boss. Live and learn.
After that, I didn't make any new parts, but spent the day reorganizing the shoppe to better arrange tools. I made a Version 3 roly thing:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-j5TXR5d/0/51120eb9/X2/IMG_5995%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-j5TXR5d/A)
It's just one of those cheapy wire carts, but with solid infills on all 3 shelves, and anti slip mats on the lower 2. Top one deliberately has no lip. Also added a backboard out of some scrap polypropylene sheet that was thrown out from work years ago. This serves as a clip board for prints and a white board for notes as needed. This is so any metrology tools don't sit on the top with other tools and bits of material, where they have a habit of working their way towards edges. Middle one is for said metrology tools, so that they can't be knocked off during normal use. Top is for whatever selection of tools I need for whatever I'm doing. Lower one actually now has my gauge pins on it for ready access. Quickly thrown together though this is, it's rather handy.
And then I allowed myself a look at the next engine project, for inspiration.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-k8RXsfM/0/47043624/X2/IMG_5999%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-k8RXsfM/A)
Mounted my collet chuck back on the lathe, and worked on the crankshaft. Even got to use my recently made carriage stop, which was hugely satisfying.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-2T2DbBj/0/47840f17/XL/IMG_6001%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-2T2DbBj/A)
Not great finishes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-B2wK7JR/0/1e16ca36/XL/IMG_6002%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-B2wK7JR/A)
Went to test it in the base casting - fits lovely - nicely held between the journals, and it spins a treat. Not too much play, spins freely. I am exceedingly happy with this.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-qZCz5xC/0/1c3c576c/XL/IMG_6003%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-qZCz5xC/A)
Now I have to mill out the center support web and turn the big end journal. I am frankly nervous that the crank will move all over the place when I mill out the support, but if it does I'll just make a built crankshaft. I had considered making a support jig, and taking out the support bridge before doing any turning - but I've read some success stories with this approach, so I just went for it.
If it doesn't move too much when I take out the bridge, then I'll make a jig to hold it and turn that center journal.
I had what I thought was a rock solid plan for finishing the crankshaft, so to that end, I popped it in the mill, to find center of the shafts, and spot the .75" offset for the crank diameter turning. Which worked great.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Ffr6JtV/0/ef19d2a7/XL/IMG_6004%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Ffr6JtV/A)
Small ER11 collets and a holder are jolly handy to have around for clearance issues.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-SBzMKc6/0/cbc32bcb/XL/IMG_6005%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-SBzMKc6/A)
A little jumping around. I decided to clean the outside of the webs to a radius while I still had the collet chuck set up.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-d6S5ZcX/0/a5c50dd3/XL/IMG_6006%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-d6S5ZcX/A)
Then cleaned the underside and removed the bridge.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-SZpZ4Hx/0/c6eb557e/XL/IMG_6007%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-SZpZ4Hx/A)
I haven't been able to bring myself to check whether the thing has moved around yet.
But anyway - went to install in the 4 jaw, thinking I could hold on to one crank web and indicate the spot mark. But no go - the one shaft going into the chuck interferes with the chuck body, and I can't get it positioned right. So, I may have to make the jig that PM Research have in their plans after all.
But I didn't feel like doing that right now, so I decided to make the piston. A failry simple part really, just needing diligence on turning the diameter.
I turned diameter, then made a "sacrificial groove" on the end face, to check depth of the grooving tool, and set up the dial. Then made the grooves. This carbide grooving tool is really, really nice.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-J6FjZNd/0/596c0603/XL/IMG_6009%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-J6FjZNd/A)
I set up a DTI to more accurately measure saddle movement.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-TkJXBmP/0/eaef2a2e/XL/IMG_6010%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-TkJXBmP/A)
This works so well, that I am clearly going to have to make a proper holder for it and use it routinely. Cheaper than a DRO, although more faffing about.
After grooving for a while, I cleaned up the face and drilled the 1/8" through hole. I wanted to do this in one set up, because it is important that the hole is very perpendicular to this face, as this is what locates the cylinder shaft - although really it's just the face that does that.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-nchFGqw/0/0af50b7c/XL/IMG_6013%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-nchFGqw/A)
Parting is such sweet sorrow.
This was the best parting op I have ever done. The parted face ended up with a good surface finish. I could have parted to length - and probably will next time. First time using this tool.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-m7VdXT4/0/ca14e083/XL/IMG_6014%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-m7VdXT4/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-T7DP8Gq/0/55601d08/XL/IMG_6015%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-T7DP8Gq/A)
Then flipped it round, faced off the little bit of clean up stock and counter bored the other side per print.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-nGXvgd5/0/0ee70e23/XL/IMG_6016%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-nGXvgd5/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-tNJfmSD/0/aaea3d57/XL/IMG_6017%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-tNJfmSD/A)
That was fun. Interesting change in surface finish on the face of the part in the last picture. Can't feel it with a fingernail - it's just from when I turned the coolant on part way through facing it. Lesson learned - perfectly fine, just looks weird. I can polish it out, but since it will be hidden in the cylinder I'm going to leave it as is.
-
The basic approach to this is simple enough - mill away two sides, drill the hole for the pin. Then I chose to shape the end by hand - I'm not very good at that kind of hand work, but for this part it worked well enough. Then cut off with some stock left, into the lathe, face to length, turn the chamfer, drill and tap the hole. Here are a few pics en route. I had to use my standard approach of "make it at least twice" before it came out "well enough". It's about 0.01" too short, but I think it will work. The tang is spot on though, in terms of length, thickness and hole position.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-c3xfpFn/0/e3ed6215/XL/IMG_5944%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-c3xfpFn/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-N9JCBzV/0/cc5ce4d2/XL/IMG_5945%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-N9JCBzV/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pMT2HjN/0/077f80fd/XL/IMG_5946%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pMT2HjN/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZVn6k2K/0/d4b95ac2/XL/IMG_5947%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZVn6k2K/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-RdsbR8m/0/3c27de02/XL/IMG_5948%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-RdsbR8m/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Dcj7J4L/0/82ed5360/XL/IMG_5949%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Dcj7J4L/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-79rhKf6/0/1e0af66d/XL/IMG_5959%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-79rhKf6/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-DksL66G/0/8e1b947e/XL/IMG_5960%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-DksL66G/A)
Made a few novice mistakes along the way, but recovered - didn't scrap the part.
Even managed to part it off, without too much drama.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-rcXTnFb/0/ed79da1e/XL/IMG_5961%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-rcXTnFb/A)
Except for that blasted stub. But no matter, I left a little stock on the back face for some clean up, since I had a suspicion that parting off might not give me the final finish I want. I'll get there on that, but I know I can skim that face to a nice finish, so not too worried. Just trying to decide whether to make a little aluminum collar to hold it on the groove diameter, or just set it up in the mill and skim it there.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-j4BTmD6/0/1a515f53/XL/IMG_5962%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-j4BTmD6/A)
Can't remember for the life of me what project that resulted from, but it just needed a little boring out to size.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-gWdFBbb/0/413e4907/XL/IMG_5963%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-gWdFBbb/A)
And when all was said and done, the backside cleaned up a treat.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Q9SqfJ9/0/16e91c92/XL/IMG_5964%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Q9SqfJ9/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-STtcJ8j/0/fbee38a5/XL/IMG_5965%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-STtcJ8j/A)
Still needs a little deburring and chamfering on the inside of the lips, but you know - overall - satisfied with this part, plus tried my hand at some new things. Win!
So, finished up the eccentric hub this morning. I wanted to ACTUALLY finish it before moving on. So I did indeed chamfer the edges of the lips, which would have been a lot easier had I left the part on the stock bar a bit longer. No matter, the little collar worked well, and let me hold it securely without damaging the lips.
Then the last thing was the 5-40 hole for a grub screw.
Getting the orientation set up using a gauge pin:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-MqwZR3v/0/de4d42cc/XL/IMG_5966%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-MqwZR3v/A)
Gauge pins are excellent tools to have. I bought a set a month ago, after seeing machinists at work establish locations using them, and then following up with an online tutorial from Joe Pie. I use these pins every time I am in the shoppe.
Then, drilling and tapping as has been seen and posted about a million billion times. Possibly more than that.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-c33VLPC/0/46bd55f8/XL/IMG_5967%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-c33VLPC/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fTm35TF/0/2b3be15b/XL/IMG_5968%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fTm35TF/A)
And there it is, hiding among the other parts, both finished, raw, part finished and of no use to anyone.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-NtCQGLL/0/0ab88cd5/XL/IMG_5970%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-NtCQGLL/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-qLKSKS8/0/b1637f53/XL/IMG_5969%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-qLKSKS8/A)
Next up is the eccentric follower.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-K7jc68B/0/2820967e/XL/IMG_5974%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-K7jc68B/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-9D2KLjj/0/54b1e856/XL/IMG_5971%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-9D2KLjj/A)
All I did today was a little bit of clean up, and some measurements of the casting to understand how much stock I have. I'm trying to take a bit more time to get familiar with castings before actually setting them up, and try and figure out any "gotchas", and figure out what stock there is where, and therefore how to get machined surfaces located relative to surfaces that will be left raw, to make sure visual appeal is maintained. This is all part of making an attractive engine, I think.
I did get one side flat on the sanding belt. The casting started off approx 0.005" parallel between the two sides (crude measurement), and there is roughly .1" of stock to take off, so should be plenty.
I have clamped it in place ready for a skim of the other side. Only a minimum clean up right now - so that I can hold it for drilling bolt holes and cutting it in half. I'll go to final thickness after the two halves are bolted back together, so that I can make sure the center of the lobes is centered on the finished part. That's the plan anyway.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-G7DD7Df/0/76118a4c/XL/IMG_5975%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-G7DD7Df/A)
Centering the part in the 4 jaw was done crudely by aligning with a dead center. This seems to have worked well - I checked run out before boring - the inside was pretty true, the outside certainly had some visual run out, but it is not a perfectly concentric part. I decided to go with it as it was. The material removal on the ID was pretty consistent straight away, so I think this worked out well enough.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-dxknxsK/0/5d8795e4/XL/IMG_5976%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-dxknxsK/A)
Setting up for the bosses.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-XcjxDgw/0/e512c2c3/XL/IMG_5977%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XcjxDgw/A)
I checked relative height of each side boss by touching off with the tool tip, and it was within 2 thou, as shown by the DRO in the pic after next.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-G7k6R6t/0/a7a89a8a/XL/IMG_5978%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-G7k6R6t/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-BdWZVNg/0/6f6e9eb1/XL/IMG_5979%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-BdWZVNg/A)
Boss face clean up:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-CTrd88n/0/a8ce3056/XL/IMG_5980%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-CTrd88n/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-qS4bFvd/0/efa2543e/XL/IMG_5983%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-qS4bFvd/A)
Getting ready to split. My prior set up was not thought through well enough, so I had to do a new set up to saw the part.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-dQsNhMC/0/f1edccde/XL/IMG_5984%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-dQsNhMC/A)
Obtaining center by using the saw, feeler gauge and DRO.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-6csmPK4/0/bcc47a2c/XL/IMG_5986%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6csmPK4/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fKPGkv4/0/928bdbfb/XL/IMG_5987%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fKPGkv4/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-CjrQBRV/0/6bd9ecf9/XL/IMG_5988%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-CjrQBRV/A)
Clean up:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-NTPcPtV/0/b649e6f4/XL/IMG_5989%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-NTPcPtV/A)
Ready for boring (probably what I'm doing to anyone looking at this thread)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Rn2b2vz/0/50644445/XL/IMG_5990%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Rn2b2vz/A)
Alignment:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-r3sZftM/0/06d753b8/XL/IMG_5991%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-r3sZftM/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-K7jfsNr/0/4e5c0b5e/XL/IMG_5992%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-K7jfsNr/A)
After boring and facing:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-QXWVvDn/0/c36d76de/XL/IMG_5993%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QXWVvDn/A)
And last but not least, the oiler hole:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZB3NkGc/0/d9358221/XL/IMG_5994%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZB3NkGc/A)
I did a test fit on the eccentric hub, and annoyingly it is tight. However, I am suspicious of burrs on edges. I'm going to give both parts a deburr session and try again, but I may have to go back on the lathe and skim out a thou, which never works well. Hopefully deburring takes care of it.
Still, not a bad day. Cheers!
-
I started the crank shaft quite some time ago. This is as far as I got it.
(https://photos.smugmug.com/photos/i-3nvQkc8/0/XL/i-3nvQkc8-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-3nvQkc8/A)
I decided at the time that I would be better off making the base first, so that the crankshaft could be turned to fit the bearing journals, and that was a good decision.
I swapped over to my collet chuck to proceed. It bums me out that I have to true up my collet chuck every time I refit it - but I suppose expecting to rely on the large threads on the lathe to accurately locate a chuck in terms of concentricity was naive at best. It actually only takes me about 10 mins to align it now in any case. The collet chuck has a set of 4 adjustment screws for fine tuning.
(https://photos.smugmug.com/photos/i-QNRrD5t/0/XL/i-QNRrD5t-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QNRrD5t/A)
(https://photos.smugmug.com/photos/i-M4599MZ/0/XL/i-M4599MZ-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-M4599MZ/A)
I can get it set up and running true enough that I can't detect run out on this DTI, and the ER collets are a lot better to work with than the 3 jaw on diameters 1" and down.
So - bit of clean up on the face:
(https://photos.smugmug.com/photos/i-76STxRd/0/XL/i-76STxRd-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-76STxRd/A)
Drill center hole:
(https://photos.smugmug.com/photos/i-5DQg6KD/0/XL/i-5DQg6KD-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-5DQg6KD/A)
And clean the diameter.
(https://photos.smugmug.com/photos/i-R7pNSBB/0/XL/i-R7pNSBB-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-R7pNSBB/A)
(https://photos.smugmug.com/photos/i-gZcW7TG/0/XL/i-gZcW7TG-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-gZcW7TG/A)
Then I cleaned up the outer faces of the cranks a bit:
(https://photos.smugmug.com/photos/i-XCLCmpH/0/XL/i-XCLCmpH-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XCLCmpH/A)
It is necessary now to turn the larger diameters next to the crank to an exact length, to locate the crank shaft centrally in the base casting. It was at this point I decided that it would really nice to have a fine adjustment carriage stop - or any carriage stop come to that. So I have paused work on the crankshaft to make one.
The plan is to get the larger diameters turned to length using the collet chuck to hold each side, then I will turn the 3/8" diameter shafts to size between centers to get best concentricity.
My 1/4" reamer arrived, so I decided to finish up the cross slide. Got it all set up, found the edges and positioned the center of the pin. Did a quick visual with a drill blank to make sure it looked centered in the casting boss.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-wDKQ8hD/0/7b64d3c4/XL/IMG_5901%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wDKQ8hD/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GZMn4JJ/0/ef228c45/XL/IMG_5902%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GZMn4JJ/A)
Then spot and drill. I drilled to about .015" undersize, but drilled out half way to that first.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-6K85D7f/0/3b8c6a53/XL/IMG_5903%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6K85D7f/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GGNMLqH/0/d6df12e0/XL/IMG_5904%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GGNMLqH/A)
Then reamed to 1/4"
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-VtDjGHt/0/65f2875c/XL/IMG_5905%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-VtDjGHt/A)
Checked with a pin gauge - got it spot on this time!
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-FhcHCcM/0/4fca2397/XL/IMG_5906%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-FhcHCcM/A)
Then set up and milled the slot.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-K5tbWkg/0/6731be80/XL/IMG_5907%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-K5tbWkg/A)
Finding hole center by using pin gauge and a feeler gauge.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-VfZpDTb/0/5dea12ad/XL/IMG_5908%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-VfZpDTb/A)
I plunged the slot to get most of the material out.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-KNxFztG/0/87ad088c/XL/IMG_5909%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KNxFztG/A)
Then cleaned up the sides and bottom of the slot. The end mill was just long enough. Worked well though.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-7ZJKSG5/0/78b2ceeb/XL/IMG_5910%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-7ZJKSG5/A)
Finished!
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-FgTG42g/0/48014ec4/XL/IMG_5911%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-FgTG42g/A)
And it even fits and slides easily up and down the rails. Will wonders never cease?
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-WjMJJ3w/0/6751b248/XL/IMG_5912%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-WjMJJ3w/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-QrVcPCM/1/ff326c50/X2/IMG_5914%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QrVcPCM/A)
Decided to finish off the valve. I had faced and pocketed this some time ago, but was not happy with the amount of error I was getting milling depths. I now have that resolved, and so......
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-kMHKZtX/0/e24863e0/XL/IMG_5915%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kMHKZtX/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HkXRhw7/0/c58f5ce4/XL/IMG_5916%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HkXRhw7/A)
I tickled out the slot until the material to be used for the nut just fit in.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-tQmGkrW/0/7b1769f9/XL/IMG_5917%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-tQmGkrW/A)
And then the same for the other slot. Again - plunged most material out, leaving 0.01" on depth, then cleaned up.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ngvGfq6/0/f5e49b3e/XL/IMG_5918%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ngvGfq6/A)
Finished part - still needs some deburring.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-nB96rz3/0/efe9c0ae/XL/IMG_5919%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-nB96rz3/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-NtFkj8Q/0/0dd47005/XL/IMG_5920%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-NtFkj8Q/A)
Then I started thinking about some other components. I was enjoying milling so I moved on to making a collet to hold square bar stock, which will be used to make linkage components for the valve drive rod.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-62xC8c3/0/5591e842/XL/IMG_5922%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-62xC8c3/A)
The overhang of this aluminum rod did cause some chattering at the end, but by making a finish pass it cleaned up fine.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-P79r7Vg/0/35176a87/XL/IMG_5924%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-P79r7Vg/A)
After taking the shaft about 0.01" past centerline, I rotated the part 45°, positioned the cutter and milled a slot.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-NZ8d9NC/0/0eea1600/XL/IMG_5925%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-NZ8d9NC/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-nvDtw5W/0/7fc82718/XL/IMG_5926%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-nvDtw5W/A)
Chopped into two pieces, and being used to hold the sqaure stock in the lathe.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-NBR2LPP/0/f08c64c9/XL/IMG_5927%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-NBR2LPP/A)
That's as far as I got today. Next stage is either the linkage components or go back to the crankshaft.
OK - I made a new holder. Same idea as before, but turned the body down to 3/8", leaving a stock 1/2" lip to stop the adapter disappearing inside the collet, per Marv's recommendation. This has indeed turned out to be a good move.
New holder:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pmkf5tq/0/37064dd6/XL/IMG_5937%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pmkf5tq/A)
And using it to start making the linkage.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-3SWqqJJ/0/bbff7ba6/XL/IMG_5939%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-3SWqqJJ/A)
The little holder is not perfect - it is not quite centered. Off by about 0.002 I think, which is really not acceptable - I could center much better than that in a 4 jaw, but my 4 jaw is a bit big for this job. I may attempt another holder. It's actually quite a good exercise for tuning in my milling techniques.
-
I went ahead and drilled and reamed the bore for the crankshaft.
It's close, but there's a mismatch somewhere. Need to evaluate my techniques more. But in the meantime I'll soldier on.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-FWWtfPr/0/49875480/XL/IMG_5789%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-FWWtfPr/A)
You can see how the nearside is mostly aligned, but the far side interior surface looks off - result of that error made much earlier on that I mentioned.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fFMfhzp/0/d6de8c9e/XL/IMG_5790%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fFMfhzp/A)
And sure enough, once the bearing cap is removed, the hole is way off center relative to the locating steps, and indeed a little off height wise, but not by much.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GcbmdZ7/0/346b0c38/XL/IMG_5791%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GcbmdZ7/A)
I think it will run. I did not seem to get any "wandering drill" when I drilled all the way through the second side - I drilled the hole out in steps, leaving some stock to clean out with the reamer. So I am confident that the bore is centered height wise to the rails. I will measure that and check.
However, going to call this "acceptable (just)" and keep going. Not sure what to do next - maybe a few of the simpler components, like upper slide rails and spacers.
I checked the crankshaft bores with a gauge pin today. It's .002 oversize, which surprises me a bit given that the hole was reamed, and in a single set up without ever moving the table. Still, that's OK, I will make the crankshaft to suit.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-5jxv2Nz/0/88e74cdb/XL/IMG_5792%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-5jxv2Nz/A)
The bore may not be as far off center as I had thought. Looking at it here with the gauge pin in place, the center of the pin seems to fall pretty close to the split line at the bottom of the bearing cap locating slot. I didn't need to chamfer the edges or anything to get the pin in - it popped right in from the top, so I think I'm not as far off as I thought. The only mystery is the difference in width of the locating slots. Maybe I'll just pretend that's an orientation feature.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-xD9GfSJ/0/e5f63a9f/XL/IMG_5795
On my base casting, from previous poor measurement attempts, the edges of the rails were not centered, leaving one rail about 0.017 closer to center than the other, although I had hit the nominal rail to rail dimension dead on. After mulling this over for months, I decided I could not stand the asymmetry any more, so I set the part up and dusted off the wider rail.
[url=https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZKVSKDn/A][img]https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZKVSKDn/0/fa3bc658/XL/IMG_5811%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-xD9GfSJ/A)
This went very well, and now the rails are even about center of the bore in the end of the casting - they are also matched in width.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-TfJtFvB/0/5d4b45fd/XL/IMG_5812%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-TfJtFvB/A)
This means that the mating part will have to be adjusted, but I'm OK with that.
Speaking of the mating part............
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-DbsQtxF/0/1797b1fb/XL/IMG_5813%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-DbsQtxF/A)
I set measured up the casting and discovered it had a good amount of stock all round, and would accommodate the changes in dimension to match my rails (I did that before adjusting the rails), so set about getting some datums.
I set up as level as possible for a first cut - I got a run iut of very roughly 0.005 along the length of the part.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZwPrMTm/0/1bac8730/XL/IMG_5814%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZwPrMTm/A)
And took off the minimal amount of material possible.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-DZLSq4P/0/a5bbd142/XL/IMG_5815%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-DZLSq4P/A)
Then on to parallels to clean the opposite side.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-rLWCnJp/0/da822694/XL/IMG_5816%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-rLWCnJp/A)
The two faces measured parallel as best as I can figure it, so I then used those surfaces to set up and register to clean the back side.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zHSLrLR/0/2fe0e6cd/XL/IMG_5817%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zHSLrLR/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-LcMmHdZ/0/dbb3fa7c/XL/IMG_5818%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-LcMmHdZ/A)
Then it was time to get on to the nitty gritty. I machined the width of the guides and the thickness in two set ups. I set up like this so that I could mill all around the guide tab on one side.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GxSSt8F/0/8ae52a61/XL/IMG_5819%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GxSSt8F/A)
The result...........
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-JNBHvBT/0/59b334ff/XL/IMG_5820%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-JNBHvBT/A)
This gave me a solid set of perpendicular surfaces to clamp the part square, and get registration to match the features on the opposite side. Notice how the 1-2-3 blocks are staggered - so that later on I can register off the 1-2-3 block face, and match the upper tab to the lower one.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-P2J2Vjg/0/392722c4/XL/IMG_5821%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-P2J2Vjg/A)
As I machined around and got close to final thickness, I actually mounted a DTI to the quill, and measured the position of the tab face relative to the 1-2-3 block - and hence the lower tab face, so I was able to keep the tabs co planar within about 0.002" as near as I can measure.
I measured the part after machining - pretty much within 0.001 to 0.002 on all dimensions. So I had to do a quick fit check.........
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-VTj28MB/0/33b4f79d/XL/IMG_5822%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-VTj28MB/A)
It's perfect!
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-6bf9Hw5/0/a9af4a65/XL/IMG_5824%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6bf9Hw5/A)
After so many bungled attempts on previous parts, I was thrilled and overjoyed at how this part has progressed. Everything is square, parallel and true, and it fits into the base casting just so well - it's a real boost. No wiggle or play, and it slides between the rails really well.
So back to the mill, and set up for the tapped hole.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bjnH2MH/0/f399350b/XL/IMG_5825%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bjnH2MH/A)
After drilling and tapping that, I popped it back on the bast, along with my temporary aluminum packing, with a drill bit inserted into the tapped hole just to get a feel for alignment with the bore.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-mMFnq2H/0/31fc7ad1/XL/IMG_5827%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-mMFnq2H/A)
I'm very happy with this part - everything went according to plan, no drama, just enjoyable machining. I think this will clean up a treat and look very nice on the finished engine.
Couple of ops left on it - first I need to drill and ream the cross hole, then mill the slot for the connecting rod. But I don't have a 1/4" reamer on hand, so I'm going to wait a bit before finishing this. Should have one this week some time.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HW5QwnR/0/9df44b6c/X2/IMG_5828%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HW5QwnR/A)
Continuing on - I realized last night that on my cross slide I probably hadn't assessed the center of the rounded boss properly with respect to the other final features on the casting - and sure enough when I did a measurement this morning, when I put the cross hole in at the correct dimension relative to the rear of the casting, it will appear off center relative to the cast feature. Haven't decided how to address it yet - I can actually shorten the casting and skim a little off the rear end, or attempt to re round the casting. Or leave it. It will be functionally fine. Probably I'll skim the rear of the casting.
Based on these experiences, and some excellent set up info on you tube, I have resolved to ask myself a new set of questions when writing out a plan for machining castings, to try and force myself to understand the casting before cutting anything.
Anyway, today I worked on the rail and spacers. I saw a technique using gauge pins to visually center the mill to casting bosses, as part of achieving a pleasing overall look as well as dimensional accuracy, so I tried that. The first rail didn't work out so well, and I altered the technique a bit for the second rail. Which frankly didn't help in the end, so I need to revisit this approach. Before machining, the underside of the rails were cleaned up on my little belt sander. That worked well at least.
EDIT: The following pics don't show every step. I cleaned the undersides of the rails first and got them flat. Then squared the side of the rail to my vise using a machinists square. I was playing with the gauge pin approach in the pictures, but then secured the part with the various clamps before finishing all the locating. Obviously I didn't attempt to drill with just the middle clamp, the parts would have ended up spinning across the shop, probably.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-8FF9CKq/0/caba4c13/XL/IMG_5834%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-8FF9CKq/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-w66mMKc/0/e346cf3a/XL/IMG_5835%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-w66mMKc/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-wQ9DVXb/0/8b7a9fcc/XL/IMG_5837%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wQ9DVXb/A)
As you can see, I ended up off center one end.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-rqFWdtr/0/e4c0dd48/XL/IMG_5838%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-rqFWdtr/A)
I still ended up off center even after drilling assessing both bosses, and then splitting differences in X and Y location.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-M4zsfMx/0/32386c1b/XL/IMG_5842%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-M4zsfMx/A)
I tried a similar approach for the center hole. The first one didn't work out, but the second was a little closer.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-N6bcDTM/0/a47b0c68/XL/IMG_5850%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-N6bcDTM/A)
Anyway, after all was said and done, and having made some simple spacers, the cross slide does go together and the slider slides without rattling, it actually fits quite well.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Mg8F859/0/201c59fe/XL/IMG_5853%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Mg8F859/A)
So, a few steps forward, a few back, but on average more steps forward than back. It can be frustrating at times, but I think I'll win out in the end.
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I've decided that having the bearing caps ready when I do the next stage of machining on the base will be a good idea, so I made a start on those. Mostly just cleaning up and squaring up.
(https://photos.smugmug.com/photos/i-TckDn3T/0/XL/i-TckDn3T-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-TckDn3T/A)
(https://photos.smugmug.com/photos/i-396JG38/0/XL/i-396JG38-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-396JG38/A)
(https://photos.smugmug.com/photos/i-R3LbJg5/0/XL/i-R3LbJg5-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-R3LbJg5/A)
(https://photos.smugmug.com/photos/i-MNQZkjJ/0/XL/i-MNQZkjJ-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-MNQZkjJ/A)
Now I have them set up and ready to receive the bolt holes:
(https://photos.smugmug.com/photos/i-KGWFfTK/0/XL/i-KGWFfTK-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KGWFfTK/A)
(https://photos.smugmug.com/photos/i-2Wb4nf3/0/XL/i-2Wb4nf3-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-2Wb4nf3/A)
(https://photos.smugmug.com/photos/i-rDscHrT/0/XL/i-rDscHrT-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-rDscHrT/A)
I decided to add the stepped feature to the bearing caps. Not really necessary, and most builds I have read leave this out, but I figured why not give it a try?
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-PcxX84W/0/63264597/XL/IMG_5757%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-PcxX84W/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-MtV3wKf/0/a4feacc0/XL/IMG_5758%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-MtV3wKf/A)
Then I moved on to machining the bearing area on the base casting. I have been having trouble getting my head around how to locate the surface of the bearing area when at an angle. I couldn't figure out how to locate it relative to the center of the bore in the cylinder mounting. But then when I was at work I saw one of our machinists setting up an extremely complex item, and he was showing me how to use gauge blocks and pins to set up different features. Armed with this fresh insight, I was ready to have a crack at this base casting again.
I set up my angle block, getting it mostly square to the machine using a 2-4-6 block in my vise, which I had already trued up. I used the dial gauge to verify squareness of the angle block.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-WMhsr7X/0/d2ed6997/XL/IMG_5761%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-WMhsr7X/A)
....and checked angle using this caliper. This was a gift from a small business I helped out with some design work. It's a handy tool, but not sure I'd splurge on it normally.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zdt4kQz/0/82598f7b/XL/IMG_5762%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zdt4kQz/A)
Before setting up the base casting, I used a pin gauge to verify the bore diameter in the end of the casting, and then used the pin gauge to measure height of the rail surfaces relative to the bore.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-CszZSxh/0/c11a70b6/XL/IMG_5763%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-CszZSxh/A)
I didn't take a picture, but I did the same thing to establish the center of the bore relative to the guide rail edges.
Then I moved it to the mill and finished the set up - I clamped it to the angle plate and then clocked it to verify squareness again.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-f88BZh4/0/6802739f/XL/IMG_5764%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-f88BZh4/A)
In this next picture, you can see a gauge block and a pin gauge in place against the machined surface where the guide gland goes. Using this, I was able to touch off against the top of the pin gauge, and establish a height to the top of the bearing surfaces. I could also calculate the position of the center of the crankshaft. Easy as it turns out - just some trigonometry. In the picture you can see a spot face and center mark I made some months ago, when I was trying to figure out how to do this. I made the center mark as a visual aid.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-hTsKqGH/0/65514344/XL/IMG_5765%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-hTsKqGH/A)
Anyway - decided to have the courage of my convictions and went for it.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-WFcQpNq/0/0fcb9179/XL/IMG_5769%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-WFcQpNq/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-4KdVrWf/0/4c787f94/XL/IMG_5772%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4KdVrWf/A)
The bearing caps fit reasonably well.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-kGCxP3C/0/7003f42b/XL/IMG_5773%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kGCxP3C/A)
One thing to notice is that because of an earlier error when machining the face where the cylinder mounts, the bearing caps are not perfectly located. I did not properly interpret the intent of the design and did not locate the mounting face of the cylinder correctly relative to the datum on the print. As a result I have had to machine more away from the bearings on the base casting than is ideal. I knew this was going to be the case, at this point I am continuing on, correcting things as I go, with a lesson learned. This should still work - it will always look a bit odd, but it's only my third engine, and 1st casting set. There are bound to be learning opportunities along the way. The next one will be better, for now forge ahead.
I'm pretty happy with how the bearing caps fit anyway.
I clamped the caps in place one at a time, and spot faced through the bolt holes, before drilling a tap hole for the screws, and tapping the threads.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-88kwcqF/0/8ab5044b/XL/IMG_5775%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-88kwcqF/A)
Then screwed the caps in place.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-drLwLDb/0/138d0ac0/XL/IMG_5777%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-drLwLDb/A)
After that, I cleaned up the outside and inside faces.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-scHcXhM/0/cc3a6900/XL/IMG_5779%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-scHcXhM/A)
Normally the clean up would be done after bolting the part flat to the table - but I decided this was as valid a method as any, and looks a little "different". Odd? I don't know - put my own slant on it. Slant. Get it?
Anyway, I also dusted off the front edges of the caps to make them match up to the base casting a little better.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-K3J5Dxf/0/f88af5b5/XL/IMG_5780%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-K3J5Dxf/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-dNPV8kV/0/2a878c23/XL/IMG_5782%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-dNPV8kV/A)
After that, I removed the part from the angle plate, and decided this was good a time as any to spot and drill the bearing caps for the oilers.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-XgmdJLp/0/6414f86b/XL/IMG_5785%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XgmdJLp/A)
This is where it sits now. It is FAR from perfect. It can, at best, be described as adequate, but while that is true, there are a lot of successes on this part, in terms of setting up square and true, and learning how to indicate off available surfaces to establish geometries. I am actually very pleased. I was at least savvy enough to not just press ahead assuming everything was right, but measured the part to find out where I was at - as such I think I can recover it and make a working engine.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bj3QPQ4/0/b8ebeb0d/XL/IMG_5787%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bj3QPQ4/A)
The two slide rails for example, are off center. But I now have the option to machine the wider one to match the narrow one, and get them both centered. Alternatively I'll machine the guide to suit. Once in place the difference in rails will not be obvious. So I need to give that some thought. Either approach means making mating parts fit what I have, and not achieving parts that are "made to print", which is a goal of mine - but I'm making progress, and enjoying myself. Therefore, I deem it a success, at least on some level.
Next - get the casting set up and drill and ream the bore for the crank shaft.
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Thanks all, I really appreciate your kind comments. Life being what it is I've not been in the shed as much the last couple of weeks, and have had to spend my time doing chores, which is a drag. Hoping to get back to the shed this weekend though, and make some more progress. Will post an update when that happens.
Stay well!
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Very enjoyable tread and keep posting. I am learning
a lot and have to go back to see what I missed.
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I am definitely looking forward to following this thread!
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Enjoying this thread . I'm a big fan of PM Research products and service. I've had positive experiences with this company. I think your coverage of the steps needed to build this engine has been great so far and I'm looking
forward to following this thread to its completion. Nice job!😊
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Since I’ll be posting in real time now, progress will be somewhat slow, but I’m glad to post pics as they become available. I keep a cheapo digital camera in my pocket while in the shop, and the pictures are a handy reference for looking back on, plus it’s fun to share them.
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Wow. A lot of time and effort in the posting alone! Thanks for a ton of high quality pictures and narrative. I'll never be a machinist but I love seeing what they do. Really an entertaining thread.
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Thanks all - high praise indeed, and much appreciated. Make no mistake, I am very much a beginner in this hobby, learning a lot all the time, but things are going well.
Thanks for the tips - might well try out the CA adhesive trick for making the replacement bronze inner head spacer that got messed up.
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Fantastic build thread, look forward to reading more on your progress.
I do like these engines from PM (particularly the earlier all bronze model), i'd love them to do a machined kit version of this engine. ;D
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Great write-up! I always find it interesting to look over someone else's shoulder and watch them make things.
One thing you might want to try for thin parts like the valve covers is to use CA (crazy glue) to temporary hold the parts to a scrap piece of round. Some heat from a torch or acetone will release the part later. Learned that trick from Clickspring on Youtube.
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AWESOME build thread!! 8) 8)
Thank you for taking the time to take so many pictures along the way :)
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Excellent post. Provides all kinds of guidance for us lesser beings.
Thanks.
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Nice setups! Keep us posted.
Len.
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Fantastic build thread.
A lot of great information.
I appreciated your candor in the narrative.
Lots of trial and error, but some great problem solving along the way.
Thanks for sharing! 🤠
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An epic thread, with full disclosure and well detailed photos!
This is excellent!!!
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I made a pin to fit to the center hole, with the idea of using it to locate the hole and therefore allow me to mill the rails accurately.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GZpBr9p/0/7384a328/XL/IMG_5449%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GZpBr9p/A)
Then I started milling the insides of the rails.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-dQ2zPV4/0/0fdb76a4/XL/IMG_5451%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-dQ2zPV4/A)
After an initial cut, I located the center of the hole again, and took a measurement to the top of the casting surface of the rails, to get a feel for how much I was going to need to remove.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Wrbbn9M/0/8b0eef34/XL/IMG_5452%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Wrbbn9M/A)
That technique worked well enough, but in the end I actually touched off the bore of the hole with the height gauge rather than using the pin.
Anyway, cleaned up the rails
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bXShF39/0/86163557/XL/IMG_5453%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bXShF39/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-N7Qg94p/0/d6803ab5/XL/IMG_5454%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-N7Qg94p/A)
I made a bit of a meal of this, with multiple set ups I didn't need, if I'd actually thought through it a bit better. I ended up taking the casting out, and turning it sideways to check the inside rail to bore center dimension using my height gauge. I was a bit worried I'd messed up because at this stage the rails were very uneven. However, it turned out I just needed to take more off one rail.
I set it all up again, and finished up.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-DC3ZSck/0/b75c00d9/XL/IMG_5456%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-DC3ZSck/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Z6Kpq5h/0/1fc427f0/XL/IMG_5457%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Z6Kpq5h/A)
Then drilled and tapped the upper rail mounting holes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-t6LVdHc/0/988f94a0/XL/IMG_5458%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-t6LVdHc/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-wdZrTm9/0/a2e71b16/XL/IMG_5459%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wdZrTm9/A)
As far as I can tell, I'm within .001" on the width of the rails, with the centerline of the rails maybe within 0.003" of center line of the bore, and height of the rails is within .001" of nominal, so not a bad go at it.
Got to think about how to do the bearing caps and crankshaft bearing holes now, so I may move on to something else tomorrow while I mull that over.
That brings me all up to date. From now on, I'll be posting as and when I get time to work on the engine - which is never as frequently as I like, and I don't move very fast when I do get the time. Such is life!
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More tinkerings. Replacement cross feed drive came today. It's wired incorrectly, such that it works in reverse. Will open it up and sort that at some point. Not a big deal, plus it was CHEEEEEP.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zDQJTkZ/0/20f99a8f/XL/IMG_5418%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zDQJTkZ/A)
More importantly, I flattened the underside of the base casting. Levelled it first longitudinally along the regions I had given a light sanding on the surface plate. Crosswise it was about 0.007" off, which I figured was not enough to worry about, and in any cae with this set up I'm levelling the base relative to the (admittedly unfinished) slide rails. Seems like as good an approach as any.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-z5RdSPJ/0/0664c8a4/XL/IMG_5419%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-z5RdSPJ/A)
Took off about 15 thou.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pp55ZmT/0/590ece7c/XL/IMG_5420%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pp55ZmT/A)
Still a couple of rough spots, but I don't think it's essential to take those out, I just want a good level surface around the whole perimeter.
Then set it up on my flattened aluminium fixture plate. Set it up so that it was as square as possible to the aluminium plate, using the slide rails and cylinder mounting face as references, as best as possible since they are not machined. Essentially "averaged" the position between the 3 surfaces, which should work well when I start cleaning material.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-FqzF775/0/677d6031/XL/IMG_5421%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-FqzF775/A)
Yes, I did support under the extremes of the casting.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-hKJhjhV/0/4a85e9d9/XL/IMG_5422%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-hKJhjhV/A)
Then went around and drilled through the bosses, lightly spotting in to the plate below. Then removed the casting, tap drilled the plate, and tapped the holes to 4-40 thread.
Hey presto, base casting now on a holding plate and ready for machining.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZmXrTmL/0/8ffd11d0/XL/IMG_5423%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZmXrTmL/A)
I need to take a file to some of the flash first, but then I will look at setting up to machine the datum face where the cylinder mounts, once I have written out my operation sequence.
I decided to make a start on the base today.
I decided to start with cleaning up the end face. This is the datum surface everything is referenced from. My plan being to get this flat, then put all the holes in it, and use the center hole to locate the height of the slide rails, and also establish the center line for cleaning up the insides of the rails and the inner surfaces of the bearings for the crankshaft.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-JM3TMzD/0/d248c437/XL/IMG_5446%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-JM3TMzD/A)
Although the drawing calls for spotfacing the end, that seems unnecessarily complicated to achieve - I suppose not much work with a boring head - but just milling it flat over a large enough area is simpler at this stage.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HPGQZ7t/0/6a609f83/XL/IMG_5425%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HPGQZ7t/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-XwT5wqQ/0/abe44bbc/XL/IMG_5426%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XwT5wqQ/A)
Then mounted it upright for the end face. I saw someone else mount one a bit like this, but I was concerned about how the plate would actually hold up. Thought I'd try it though.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ht5D6nJ/0/cc463148/XL/IMG_5427%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ht5D6nJ/A)
I did mark up the end as a visual aid. I like to establish points from edges using an edge finder, and then center drill locations, rather than try center punching them. But I thought it might be a good sanity check to have this marked out to refer to.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-XqKDk7C/0/34c4441b/XL/IMG_5428%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XqKDk7C/A)
Worked out OK. I actually found center by measuring the part, and then using an edge finder, and indexing from there, to keep the center point central, but my back up scribing was reassuring to have.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-tLSZzB8/0/140f05c6/XL/IMG_5430%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-tLSZzB8/A)
However, the plate did start to vibrate, so I decided to remount before going further.
I have this angle plate. I crudely set it up first
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-QnrgGNj/0/7cca5a4f/XL/IMG_5431%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-QnrgGNj/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pRXFZfQ/0/36ccd0c9/XL/IMG_5432%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pRXFZfQ/A)
Then secured the fixture plate to the angle plate, and used the actual part face to get everything squared up, level and true.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-L5JTpr2/0/3d939ff5/XL/IMG_5433%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-L5JTpr2/A)
I found center of the part again, using a co-axaial indicator, and then started spotting holes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fx936K4/0/1db2535b/XL/IMG_5434%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fx936K4/A)
I used the geometry approach to establish the coordinates for the bolt circle pattern, which is very simple on a six hole pattern. My little Zeus book has these all predefined for easy reference.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-RfGqn6f/0/d9dfb349/XL/IMG_5436%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-RfGqn6f/A)
Anyway, a bunch of counting of dial turns later, being sure to remember to take up backlash, and there we have it.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-gTLZMgs/0/b74d86d2/XL/IMG_5437%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-gTLZMgs/A)
Test fit:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-dhBnpRV/0/fa007e18/XL/IMG_5441%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-dhBnpRV/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-42DjLdj/0/9851cead/XL/IMG_5442%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-42DjLdj/A)
Which looks OK to me.
Then I spent a little time cleaning up the boss surface.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-JqZ2h2V/0/97d7fcef/XL/IMG_5443%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-JqZ2h2V/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Mmb2RVB/0/c03c995d/XL/IMG_5444%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Mmb2RVB/A)
It seems to take me an exceptionally long time to set jobs up. For instance setting up the angle plate and getting the face of the base casting level and true was about 2 hours. But maybe that's just a matter of practice. At this stage I'm more interested in getting the set up right, than how long it takes to do it. I'm pleased with the last few workshop sessions results.
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Milled out the pocket anyway. Got the size of the cutout within 0.005" on all sides, within 0.002" on depth and centered on the part within .002" each direction. Always good to see how close you hit the mark.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bWKgXnQ/0/0638fac3/XL/IMG_5392%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bWKgXnQ/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-2qTvT48/0/b10102fc/XL/IMG_5394%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-2qTvT48/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-jjFfV2S/0/87844a2a/XL/IMG_5395%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-jjFfV2S/A)
Thinking I'll polish up the main face on a surface plate before it goes in to service.
Then had a try at some flycutting. I have a piece of aluminum plate that I want to use for holding the chassis casting. I started sanding it flat a while ago, but it quickly became apparent that it was going to need a fair bit of material removal. So, I ground a tool according to the geometry I found on Toms Techniques website, and had a try.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-X225Xvg/0/a401a9ca/XL/IMG_5397%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-X225Xvg/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-G3q3Gkw/0/a0138eb7/XL/IMG_5399%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-G3q3Gkw/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-W6Tn5qr/0/d5d83da7/XL/IMG_5401%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-W6Tn5qr/A)
I don't know much about interpreting the cross hatch pattern, but I think this is not too bad. The casting no longer rocks on the plate, although I still have a bit more clean up to do on the underside of the casting to get it set down all around, but progress made anyway. Only problem being the cross feed motor died shortly after I started, which is a bit vexing, so I had to hand feed everything. Probably just a contact brush issue I think.
I made a start on the crankshaft tonight for no particular reason. It's just what I felt like working on.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-kwrH9kL/0/3bc1579b/XL/IMG_5412%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kwrH9kL/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-j9dW6ns/0/80fab6d8/XL/IMG_5413%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-j9dW6ns/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-4xc5JsF/0/c95ce1fe/XL/IMG_5415%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4xc5JsF/A)
Not sure I'm entirely happy with that set up, so I'll look at that again before any more turning. Probably put on a cutting tool with a smaller radius for a start.
Also tonight, a little more flycutting to level out both sides of my jig plate.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-w6X3fTN/0/e37f4112/XL/IMG_5416%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-w6X3fTN/A)
My cross feed drive broke down, and is under investigation. I can probably repair it - better that than $450 for a new one.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fFJB7sp/0/a6e8c419/XL/IMG_5417%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fFJB7sp/A)
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I made a simple collet to hold the snout of the spacer.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-NGQ7TcF/0/514ab4b9/XL/IMG_5360%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-NGQ7TcF/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fqTnHmk/0/a79e184f/XL/IMG_5362%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fqTnHmk/A)
I could only take light cuts, but this worked, and the part was finished.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HmRzR2Z/0/16b1b620/XL/IMG_5363%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HmRzR2Z/A)
I have been wondering about getting hold of a 3" chuck, which I could then hold in this chuck (a 6"), just to make it easier to hold smaller parts. I don't know if that's a good idea or not.
Anyhow, then I went back to my cylinder. I made a mandrel to hold it, and set up on rotary table in the mill. Here I'm squaring the steam chest, to get the bolt pattern properly aligned.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Vf6RDtJ/0/5e8e15d0/XL/IMG_5370%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Vf6RDtJ/A)
I did have to mill chunks out of my "nut" to allow clearance for my center drill, but I knew I was going to have to do that, in order to maintain some overlap and clamp the cylinder well.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-sKpnZDR/0/d946cdcd/XL/IMG_5371%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-sKpnZDR/A)
I tapped the holes by hand, but using the mill to keep the tap square. I can disengage all the gears so that I can turn the chuck easily by hand.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HTDbG4D/0/16891877/XL/IMG_5372%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HTDbG4D/A)
Family shot, such as it is. 3 parts and a red headed step child. ;D The bronze part that was ruined will go on the shelf marked "sacrifices to the god of machining".
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-4HtNbVd/0/e631fe28/XL/IMG_5375%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4HtNbVd/A)
And the cylinder head even fits.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zbLcWnM/0/41dfa551/XL/IMG_5376%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zbLcWnM/A)
I actually managed to get the holes for the outboard end lined up correctly. I thought I would have to skew them because of the poorly positioned steam ports this end.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-d2FchSS/0/74f60e60/XL/IMG_5377%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-d2FchSS/A)
It even fits the other end (although it doesn't go there). Just checking hole positions.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Kvmwd7D/0/4737b848/XL/IMG_5379%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Kvmwd7D/A)
Well, that was good. Just got to tap the gland mounting holes and steam chest cover holes and the cylinder is complete. Now to decide which part to make next.
It seems like I only went to the shed 5 minutes ago, but 2 days seem to have slipped past. :shrug:
It does take me a long time to make parts, but there’s a lot of other things going on as well.
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Got it up on the mill and put the bolt circle in.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-v2m85ZM/0/b034d6de/XL/IMG_5350%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-v2m85ZM/A)
First time I have aligned using the conical center finder, and it really works well, just using your fingers to feel the alignment. A quick check with a micrometer in two directions verifies location. You all know this of course.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fwBQRnW/0/8cae07b2/XL/IMG_5351%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fwBQRnW/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bQcv3bD/0/a5cf3c03/XL/IMG_5352%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bQcv3bD/A)
The bolt hole pattern aligns very well indeed with the one I put in the outboard cylinder head, which pleased me to no end. Good test of repeatability of the rotary table and mill set up.
Then machined the snout to size. Parting off was a gentle and slowly slowly approach.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-WVQt9DG/0/ee1a23eb/XL/IMG_5355%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-WVQt9DG/A)
Then cleaned up and brought to size with a knife tool.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-GTQ93z2/0/3a2bad7e/XL/IMG_5356%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-GTQ93z2/A)
Turned the part around, and brought the part to final thickness.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-6tq8dNR/0/f6d908a5/XL/IMG_5357%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6tq8dNR/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-F8gHGqM/0/38c67d35/XL/IMG_5358%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-F8gHGqM/A)
Pretty happy with the final finish on that.
One last step to do, which is machine a step on that face. Hopefully get to that tomorrow.
Much better progress today. I’m sorry my posts aren’t a bit more interesting, but I'm working at the very basic end of the spectrum of model engineering, in terms of knowledge, experience and skill, but I'm having a good time, and even having some success - if not very consistent success, so I think that counts for something. Still going to make this engine run. Although that day seems a long way off yet. ;D
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Lathe is all back together - feels a little better now.
(https://photos.smugmug.com/Stuff/Shed/i-kJ65kJt/0/18fe550e/XL/IMG_5316%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Stuff/Shed/i-kJ65kJt/A)
I've been reorganizing as well - moving some of my raw material off the wooden shelves, and sorting out tool storage there. Still got to do the lower shelf.
With the lathe back together I made some progress on the cylinder.
I mounted it on the angle plate. I used a 1-2-3 block as a stop, and made sure that was parallel to the table, then repeated the parallelism check on the face of the cylinder once I had it clamped in place.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bJRmXjw/0/256da864/XL/IMG_5311%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bJRmXjw/A)
I used an edge finder to find the center of the high edge of the bore, and then after a little trigonometry calculated the position of the centers of the two port holes, and spot faced them with a 1/8" end mill, then drilled down to the slot that was previously milled in the steam chest.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bRBBXL8/0/a796316c/XL/IMG_5313%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bRBBXL8/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-wSWC5m7/0/f3edf1ad/XL/IMG_5314%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wSWC5m7/A)
I am pleased that I hit the slots dead on - right at each end of the slot. It was a real fulfilling sense of achievement when I felt the drill break thru into the slot.
Now to turn it over and repeat on the other side. This part is actually close to completion! I hope to drill the other ports tomorrow, and do a little more turning on the inboard head.
I drilled the other two port holes today, but got them off center. They will still work, but I'm getting a bit tired of making parts "that will still work". Not sure where I went wrong - whether it was in finding center or if I just indexed too far when moving to the drill point. I'm not even going to post pictures, too embarrassing. I might go ahead and buy a new casting, on the basis that implementing what I've learned on the first one will make for a really nice second one, however I shall be extremely disappointed if I have to replace every casting in the kit.
Which brings me to my second issue of the day, and a real disaster.
I picked up the inboard head again, and was having a good time with it. I cleaned it up, got all diameters and faces true, and even drilled and reamed the through hole.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-8GChGmH/0/7d6da5a9/XL/IMG_5324%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-8GChGmH/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-XhzBvKL/0/187f2910/XL/IMG_5325%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-XhzBvKL/A)
Then brought the disc to final thickness.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-JXsVB4c/0/50f54bfb/XL/IMG_5326%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-JXsVB4c/A)
Got a lovely finish on it, and the thickness within .001" of dimension from the print. Great!
Proceeded to turn down the face some more to make the step, and that was going well, or so I thought, when suddenly my thickness measurements started moving around back and forth.........
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-hWWf6jk/0/09db0b44/XL/IMG_5329%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-hWWf6jk/A)
Blast, and quite a lot of other words.
I don't really know how this happened. The part never grabbed, I was taking nice light cuts, everything seemed to be fine.
On top of that, I discovered while making this that there is still something wrong in the carriage of my lathe. The handwheel drive is not at all repeatable - go to move the carriage .020" - it moves .01 and change. Move it back down the bed and bring it back to zero, it ends up going past zero by .02" or more. So a key or a pin has broken in some gear or other in the saddle. I'll take that apart again before attempting to remake this.
At least organizing that area of the shop went well, and the cross slide adjustments worked well.
I'm not giving up. I'm going to finish this engine, and if I have to remake parts along the way, so be it.
Anyway, lathe is fixt. Found a sheared pin in one of the drive shafts. :Mad:
Easy enough to fix, so that's something. And I have very quickly turned a piece of aluminium to replace the inboard head (not going to use the replacement casting just yet........). Will finish this after a bit of lunch.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bdw58SW/0/727236a0/XL/IMG_5346%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bdw58SW/A)
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Yesterday I fixed up my rotary table, and made a successful test, so today I went live with it.
I finished the step on the outboard cylinder head, so that it fit nicely in to the cylinder.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-J8c53wW/0/f90a1293/XL/IMG_5293%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-J8c53wW/A)
Then I turned it round and dressed up the outside a bit.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Rdwp5dJ/0/7002c921/XL/IMG_5294%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Rdwp5dJ/A)
I decided on just enough clean up to provide a flat surface for the clamping nuts when the time comes. I felt it maintained the "cleaned up casting" look. Maybe it should be cleaned up a bit more. Don't know yet.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-C4BSVkh/0/db006125/XL/IMG_5296%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-C4BSVkh/A)
Anyway, on to the rotary table, and spotted and drilled the bolt holes.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-VQtJfxD/0/ebd826e6/XL/IMG_5297%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-VQtJfxD/A)
Something got out of position, because when I went in to deburr the holes, the chamfers are definetely out of synch with the main bolt hole pattern. Not that they will be seen on the finished engine, but these kinds of errors and mishaps really grind my gears. Must do better than this. I bet I moved the slip ring 5 degree dial collar on the crank handle - it is only spring loaded, and has has no locking screw. I may well add one to try and avoid this.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-7f9Hx2p/0/9a76b649/XL/IMG_5299%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-7f9Hx2p/A)
I thought I would make a start on this part.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-R4SB4jx/0/d5b84557/XL/IMG_5300%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-R4SB4jx/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-8MVNDTF/0/df10ad25/XL/IMG_5301%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-8MVNDTF/A)
Cleaning up and getting ready:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-hJ8pSkf/0/60b44f17/XL/IMG_5302%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-hJ8pSkf/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-JDcdr4J/0/9681aad1/XL/IMG_5303%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-JDcdr4J/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-5ft75cs/0/4cd6b9e2/XL/IMG_5304%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-5ft75cs/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Cm5k622/0/7fe4f25d/XL/IMG_5305%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Cm5k622/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-hHQ9t76/0/bfa7c1f1/XL/IMG_5306%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-hHQ9t76/A)
Lots to do yet.
Anyway, something that has been bothering me is the backlash on my lathe cross feed. The cross feed just feels really slack, and then today the backlash seemed to increase on the main carriage. When I turn the dial on the carriage, the backlash gets taken up, I can feel everything engage - but then I can turn the dial a bit more, feeling a little more resistance, before it really starts to drive. I was worried that a gear might be slipping on a shaft or something, so I have taken most of the saddle and cross slide apart. I want to just make sure everything is set up right before going any further.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-vvKnkX3/0/389bf51a/XL/IMG_5308%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-vvKnkX3/A)
It will be good just to look everything over and make sure all is well. Seems like I spend more time setting up my machines than actually making things.
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Anyway, pressing on today. I set up with a very close fitting rod to let me locate the center of the bore.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-L2g2FzW/0/a7c4f82e/XL/IMG_5263%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-L2g2FzW/A)
Using the two clamps allowed me to adjust the level of the top machined surface of the steam chest (and therefore the base of the steam chest).
I aligned the V blocks supporting the rod to the Kurt vise using other V blocks - which worked really well. I did double check that the faces of the cylinder were parallel to the X axis of the table.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Qpt872D/0/e6dd62ba/XL/IMG_5264%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Qpt872D/A)
Clearance was a problem with this set up. It worked out fine for the larger slot, although I had to extend the milling cutter a way.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-cVTxPBS/0/fa359287/XL/IMG_5265%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-cVTxPBS/A)
Got the slot done. I also noticed that I could clean up the one side of the chest a bit more, and put radii in the two corners. I may well do that at some point. Should have done a better job up front.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-HW2CDR8/0/6e4578fb/XL/IMG_5267%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-HW2CDR8/A)
Of course - having finished it, I realised that the supplied drawings specify the slot with from the outside quadrants of the radius at the ends of the slot - whereas at work we always dimension slots from the center of the end circles - which is because that is most useful to the mill operator. So unfortunately this slot is too wide. However, I think it will still work. I'll make sure the valve suits the slot. And in future, I'll be more careful to check all dimensions on supplied prints as to how they are defined.
I'm also disappointed about the ridges in the slot, which are a result of milling the slot in stages. I wonder what I could have done to avoid these ridges? I locked down the cross slides when milling this, but maybe there is a backlash adjustment I need to make? Need to give that some thought.
So on to the smaller slots. And here I got in to some difficulty. I simply could not get close enough with my quick change collet holder, so had to resort to using the standard Jacobs chuck for milling the two small slots. I may have to obtain some standard R8 collets - or a better approach might be to make / modify some clamp bars to a lower profile for small work.
I did have to move clamps around throughout the process, but I managed to get the job done.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pvxsL7w/0/0a0f7caf/XL/IMG_5269%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pvxsL7w/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-dK5BBjT/0/d323f7a7/XL/IMG_5270%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-dK5BBjT/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-6RD2B82/0/0867f9e2/XL/IMG_5271%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-6RD2B82/A)
Finished:
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-kMZFdmk/0/96c3aab6/XL/IMG_5272%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-kMZFdmk/A)
Not the prettiest. Improvement needed of course. However, depth of the short slots was only 0.005" over nominal - so getting the hang of dealing with quill backlash, which is encouraging, and everything seems to be in the right place.
Close up of the ridges
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-4ZR9GwX/0/41d16d90/XL/IMG_5273%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-4ZR9GwX/A)
I don't think these will affect the operation of the engine, but obviously I'd like to improve on that.
To finish up for the day, I put the side holes in.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-gkZTKSx/0/8375dff0/XL/IMG_5274%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-gkZTKSx/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-KWQR8FH/0/7690e640/XL/IMG_5275%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KWQR8FH/A)
I now face the challenge of making four porting drillings, at 20°, to port the two small slots to the bore. I started looking at the use of an angle plate I have, but did not get very far. I think I want to use the tight fitting rod to find the bore center to locate the ports. Anyway - more thought needed, and hope to put some time in on this tomorrow after getting my chores done.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-8XKCLkS/0/6969cb39/XL/IMG_5277%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-8XKCLkS/A)
I've got this, but I'm not seeing a way of using it and keeping access to the bore, which I need in order to position the ports. I think.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Q4Z2d5D/0/e1d3af0a/X3/IMG_5278%20%28Large%29-X3.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Q4Z2d5D/A)
Thanks for looking. As usual - mixed feelings. Some things went OK, other things didn't turn out as well as I hoped, but I think I'm still looking at a functional cylinder to get to a working engine at this point. However, I'm desperately trying to make really nice looking parts, not just functional ones. I'll get there.
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I am leaving the piston aside for now, although good progress has been made with steel finishes.
Today I reviewed the cylinder, and elected to continue. I had not yet machined the cylinder to length, so that was today's job.
First thing I did was just to check parallelism of the faces and the bore, to reassure myself they had been made correctly - which they had. I was happy about that.
Then I mounted the cylinder in the 3 jaw, with my Edge Technology chuck spider to hold it square, and machined the opposite face.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fFhxjjd/0/741b49b9/XL/IMG_5253%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fFhxjjd/A)
The gland boss in this picture has to remain proud of the cylinder face by 1/8", so I'm turning from the inside out. I had originally thought about milling this face, but this seemed a better technique in the end. It worked out fine - I got the length within 0.001" of print according to my micrometer, so I'll take that.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zghZm3k/0/2dde0798/XL/IMG_5255%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zghZm3k/A)
I decided to start work on the various bosses and slots. The gland boss still had about .013" to come off to get to the right length, and although I could have done that while turning the face, I finished it in the mill.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-zZLvzwv/0/b30aba98/XL/IMG_5256%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-zZLvzwv/A)
For Christmas, I got one of these handy dandy gadgets. I must say, it makes centering a bore or a rod on the mill an absolute breeze.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-5dmjv8Q/0/a138bd21/X2/IMG_5257%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-5dmjv8Q/A)
I then proceeded to center drill and drill the features on the gland boss.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-rtZBvq6/0/1defbaea/X2/IMG_5259%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-rtZBvq6/A)
Unfortunately the gland boss ended up slightly off center relative to the holes and the face of the steam chest. When I machined the steam chest I did not quite judge the height of the face right. I don't think this will matter in the end, just doesn't look quite perfect. The drawings were a little unclear in that regard. Part of the learning experience. They should really give a dimension from the center of the bore to the face of the steam chest.
I also cleaned up the faces of the port bosses, but decided bot to drill the holes just yet.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Hd8snw8/0/20e15478/X2/IMG_5260%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Hd8snw8/A)
What I want to do next is mill the 3 slots in the base of the steam chest, so I started getting that set up.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-VpBcBhx/0/9de31137/XL/IMG_5262%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-VpBcBhx/A)
This is as far as I got today. I need to level the steam chest, then I can find the center of the chest from the cylinder faces. I think I will actually clamp the cylinder in a V block or something though, so that I can find the center of the bore as well. I should have machined the slots when I had the cylinder set up for the steam chest perhaps, but I should be able to get where I need to.
Anyway, good to be working on the engine again, hopefully more progress tomorrow.
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I spent the week mulling this over, poring over the plans, and decided that I didn't have my machining sequence optimized. What I failed to do, was interpret the relationship between the position of the steam chest floor and lip in relation to the cast boss on the inboard end of the steam chest. If I want the gland centered in that boss (and I really do), then it is best to machine the steam chest to that feature. That means boring the cylinder, then drilling at least a center hole position in the boss, and referencing from that.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-wMBbKz5/0/99ccf362/XL/IMG_5057%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wMBbKz5/A)
Well before tearing down, I measured the height of the boss, then measured the lip and floor of the steam chest, and found that if I want to center the gland in the boss, I still have 0.024" of steam chest to machine away. That gives me enough material to go back to the lathe, machine the bore and outboard face, and then come back and true everything up and keep going, so no harm done.
I decided that since it was all set up, and that I am pretty sure I can get the faces of the cylinder true to the lathe chuck, I might as well drill the bolt holes. So I did, using the cover as a template.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ZZFMX3M/0/c71d7362/X2/IMG_5038%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ZZFMX3M/A)
So on to boring.
Except - that's a pretty new operation to me, and I haven't had a lot of success with it. Time to change that.
I spent a good bit of time on saturday reading up on making boring bars and bits. I discovered in the old, mostly crappy lathe tool kit that came with the lathe, that I had a 3/8" boring bar, with a 1/8" square HSS tool blank in it. Perfect!
I made several cutting tools, and had several attempts at boring out a piece of aluminum rod that I had left over from a project. It already had a 20 mm hole in it, so this gave me a good practice piece.
After several dismal attempts I shut up shop and spent a few hours doing more research. Armed with some internet pictures and some advice from books etc, I returned to the shop this morning, and had another attempt at grinding a tool. This is really tricky on a small tool blank, and doing it freehand, on my bench grinder which has very curved edges on the wheels, but I made this thing.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-vRZVLzV/0/90d427a2/X2/IMG_5040%20%28Large%29-X2.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-vRZVLzV/A)
It doesn't look very impressive, but the clearances and rakes are more or less kind of sort of where they need to be.
A few test cuts in aluminum showed that if I make 2 cuts for each diameter position, I can get a good finish. My reading suggested this was necessary, to account for boring bar flex. The first cut tends to be a bit rough, but the second one cleans up well.
I still didn't want to rush on to my cast iron cylinder just yet, so I gave it a go in a piece of stainless pipe I had laying around.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Lmfwb56/0/de3f3b81/XL/IMG_5041%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Lmfwb56/A)
The finish actually felt very good to me, so since I had everything set up I took a deep breath and decided to have a try at cleaning the bore.
Here is my set up
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-5rMbfMs/0/0ac8c96a/XL/IMG_5044%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-5rMbfMs/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-hptdf2j/0/4f4d279a/XL/IMG_5046%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-hptdf2j/A)
As you can see, I cut off the excess piece of tool blank from the far side, and I have to have a goodly amount of overhang of the tool bar. The bore has plenty of material to take out, so I felt OK making a start with a light cut to see how things went. If it went poorly I could abort and still save the part. I set up the cylinder in the chuck by using parallels behind it on the machined face, and pushing it against them using a dead center in the tail stock. This had the part running very true in terms of the machined cylinder faces relative to the chuck.
After a couple of passes, I judged that everything was proceeding satisfactorily enough, that it was time to make a bid for the 1.000" bore.
To help, I noted the crossfeed dial position each time, and measured the bore using a bore gauge and micrometer, noting the nominal cut taken and any error. I wanted to get a feel for variation in diameter so that I could account for that as I got close to size.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-W88JpdC/0/a6172dd5/XL/IMG_5052%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-W88JpdC/A)
It worked out well. Certainly I sneaked up on the bore size, but I got it, and I think the finish is acceptable. (Hard to tell from the blurry picture).
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-KxZwx3B/0/0c44e24d/XL/IMG_5051%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-KxZwx3B/A)
The icing on the cake was testing the bore with this aluminum plug. The plug measures 0.999" on my micrometer, and it slid evenly through the whole cylinder, with no detectable play, and no binding as I pushed it through. So I'll call the bore good. I may hone it at some point, but I'll be honest, I feel like my machine set up efforts, and taking the time to test new techniques are really paying off.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-7GNs34C/0/f230ff96/XL/IMG_5053%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-7GNs34C/A)
Since it was all set up so nicely, I decided to face the cylinder to length on the outboard end. I did this by measuring from a scribed center on one of the side port bosses. The inboard end will be machined to length from this new turned face.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-3KcGXrH/0/d7b1a56e/XL/IMG_5054%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-3KcGXrH/A)
Finished outboard end. The machined away boss that end is not used on this engine.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-35ttFmq/0/17c6c85f/XL/IMG_5055%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-35ttFmq/A)
Colour me happy.
While in the shed, I have also made a start on cleaning up the base. Just by using emery paper on my surface plate. I need to take a little bit more off, just enough to make the underside flat with some clean metal all around.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-tVtkVpn/0/5d9a1745/XL/IMG_5058%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-tVtkVpn/A)
While digging around I found a nice piece of 3/8" thick aluminum, left over from some work project or another. I'll flatten the top of it, and use it as a jig plate to hold the base casting.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-fbZhqzk/0/6555bd35/XL/IMG_5043%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-fbZhqzk/A)
I also found this lovely piece of cold rolled steel, a chunk of which is going to be used to make some new boring bar holders, based on the documents kindly sent to me by Baner.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-pjbnTCR/0/b1dba538/XL/IMG_5059%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-pjbnTCR/A)
So, some success. I feel good about all this. Next step is to machine the inboard face and gland to length, then I'll get back to the steam chest and finish that.
One thing that is very apparent, is that I really need to make the grinding table for my bench grinder. I have Howard Halls book - Tool and Cutter Sharpening (Workshop practice series 38) which has a nice design in it. That will really help for getting cutting bits made properly, once and for all.
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Well, I just got done milling the steam chest out, and I must say I'm happy with how this has gone. I had to put together a coordinate diagram for it, and then carefully keep track of my handwheel positions, because I don't have DRO's (not likely to add these in the foreseeable future), and also made sure to write down diagrams to remind me which way to turn the handles (sounds obvious but I've fallen foul of that before).
Anyway, I'm 2 thou over on the depth of the chest, which is within my general tolerance goal of ±0.005 so I'm pleased. Looks decent too, in my opinion.
Now I'm trying to decide how to center the slots in the bottom of the chest. I can easily do that from the sides of the steam chest, but then how to center the bore in relation to that? Need to give that some thought. I have a feeling that if I center the slots in relation to the casting OD, that everything will line up well enough. Have to double check dimensions on the valve etc, make sure everything will work if I do that. Also need to get some small milling cutters, so this is it for now. Got to go and do some chores. Leaving the cylinder where it is for now, because I want to mill the slots, and also drill the holes for the cover before moving it.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-bMFWwk6/0/0163ed91/XL/IMG_5034%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-bMFWwk6/A)
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I made a start on the outboard cylinder cover. A tricky item, being a somewhat thin casting. I turned the OD in 2 stages - from one end, then flipped around. I couldn't think of another way of doing it.
Since the part has to be machined down to a step, that more or less got rid of the line on the OD from the two stage turning, and the OD is close enough that when I clean and polish parts that mark will go away.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-nGFWFtL/0/782f5b64/XL/IMG_5023%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-nGFWFtL/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-3b4MbtM/0/056b9f1e/XL/IMG_5025%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-3b4MbtM/A)
Mostly finished part. I actually need to skim the face and shave 3 thou of the small diameter. I didn't plan to do it this way, I had intended these turnings to be finished. However, since I am only a few thou oversize, I'll wait until the cylinder is done before dressing this up.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-2kNcJ3k/0/ce823619/XL/IMG_5026%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-2kNcJ3k/A)
So I turned my attention to said cylinder. I have been scheming about this part for a while, so I decided to proceed.
Started by dressing some of the uglier bits of flash on the belt sander.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-ptFJMFG/0/159924c2/XL/IMG_5027%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-ptFJMFG/A)
Then used a dead center to get the casting mostly straight in the chuck. There is plenty of material to get a clean bore, so this seems to be as precise as needed to start making datum faces.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-P9ptBqV/0/51217145/XL/IMG_5028%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-P9ptBqV/A)
I basically just did a minimum clean on each end, leaving plenty of material, to get parallel faces for holding in the mill. My plan is to get each end to length once the steam chest is made, and reference everything off that.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-FNsj9sW/0/79538106/XL/IMG_5029%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-FNsj9sW/A)
So I set the cylinder up in the mill. I used a height gauge to get each side of the steam chest area level before starting to clean up, then took the top close to the valve gland boss.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-wsp3TB8/0/3388297f/XL/IMG_5030%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-wsp3TB8/A)
Then I started cleaning up the inside of the steam chest.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-D9sH3bc/0/0cdacb23/XL/IMG_5033%20%28Large%29-XL.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-D9sH3bc/A)
Now that I have straight edges, I can locate those accurately, and mill the sides and bottom of the chest to depth. Then I'll move on to the port slots.
Fairly happy with how things are going at this point.
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This is my first engine from castings. I actually started this in the back end of 2018, but progress has been slow. Model Engineering has been my "second hobby" for a long while, but for various reasons it is moving up to number one spot, which was always the plan. Motorcycling is ramping down. Anyway, there now follows a catch up series of posts, copied from another forum I am on, and I hope you enjoy the journey.
This is the advertised finished model, from the PMR site. It didn't grab me straight away, but has grown on me somewhat.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Ht2tcLP/0/26fe7853/L/STEAM-ENGINE-1-L.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Ht2tcLP/A)
I bought this kit back in 2015, got waylaid a bit, but am finally ready make a start.
I'm sure this will be a slow project, but I am keen to tackle the challenges posed by a set of castings, and today I actually took that tentative first step.
Here is the kit
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-9v9XXh9/0/4ed5ea03/L/IMG_3636%20%28Large%29-L.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-9v9XXh9/A)
And, since a journey of 1000 mile starts with a single step, I'll start with this.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-z9NhDWs/0/f674e467/X3/IMG_3638%20%28Large%29-X3.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-z9NhDWs/A)
Got the 'ol hacksaw out, and separated these parts. This one is getting some attention today.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-Pj6gS84/0/1637f9bf/X3/IMG_3639%20%28Large%29-X3.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-Pj6gS84/A)
All I've done so far is square the sides up, and clean up the sealing surface.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-2QXTXWC/0/85608dd9/X3/IMG_3641%20%28Large%29-X3.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-2QXTXWC/A)
Annoyingly, the camera makes the machined surface look a lot rougher than it is. Can barely feel the machining marks. Even so, I'll give this a clean up and polish.
Now with added holes. I'll call it a success - machined a new material (cast iron), and got the holes in the right place. The casting is a bit rough. I fettled it a bit on the corners but a little more clean up work needed there. The bosses for the screws nearly disappeared entirely, and I'm tempted to machine the top surface around the whole perimeter to clean it up, but for now I'll leave it as it is.
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-FhHqwMf/0/cb82fefe/X3/IMG_3642%20%28Large%29-X3.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-FhHqwMf/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-VvcXzzr/0/95675c8f/X3/IMG_3643%20%28Large%29-X3.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-VvcXzzr/A)
(https://photos.smugmug.com/Steam-Engines/PM-Research-1/i-d6VHkKB/0/a3ea47a1/X3/IMG_3644%20%28Large%29-X3.jpg) (https://propforward.smugmug.com/Steam-Engines/PM-Research-1/i-d6VHkKB/A)