Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Yes, that little globe valve kicked my ass.  I had to swallow my pride and order a pre-made one which was done quite nicely.  Learned some tricks from that one as they don't make them quite like they show in the plans, so hopefully next time I can make a good one.

Fixtures are a must for machining the pipe castings without setup nightmares.  If threading, you need to decide what thread type you are going to use.  I imported my taps & dies from the UK as they were a good bit cheaper than PM.

Quote from: ShadetreeMotorcycle on February 16, 2021, 04:04:25 am

I have had my PMR fitting kit ordered from ministeam for a couple days now, and want to make a fixture (for machining) to hold the 90 deg fittings tonight after work...looking the fittings over and taking some measurements, I suddenly realized they did not send my Globe valve kit! I am usually real good at taking inventory of a shipment...a quick call to Susanne at ministeam, she said she had my Globe valve on her desk with a note...she knew she had shorted someone as it was on the ship table after everything left...but she had no idea who...said she was expecting a call...Lol! 

My globe valve kit should be in the mail today.

Let me know how you do on the globe valve build Ben , I believe that one is above my current skill set. 

Will do! My last place of employment had 7 lathes and 3 of them where Collet lathes. I will not even attempt the Globe valve kits until I have access to collet type lathe. I have informed my current employer they Need a collet lathe, a 3 jaw chuck is not prefured for this type of work...I have a bid in for a old bench collet lathe in great shape, always wanted one for home use. I will snap some photos of my setups when I do machine them...there Are some tricks to making that long center stem and the tiny threads!

Yes, that little globe valve kicked my ass.  I had to swallow my pride and order a pre-made one which was done quite nicely.  Learned some tricks from that one as they don't make them quite like they show in the plans, so hopefully next time I can make a good one.

Fixtures are a must for machining the pipe castings without setup nightmares.  If threading, you need to decide what thread type you are going to use.  I imported my taps & dies from the UK as they were a good bit cheaper than PM.

Thanks for the heads up on the Globe valves! Now you got me wanting to order a complete Globe valve...If they have found a Better way to machine them and not updated there kit drawings, I want to know as I see me needing Several of these Globe valves in the future! I really love the look of PMR Globe valves.

Obviously I am missing something .
Shadetreemotorcycle talks about needing a collet chuck for machining the PM globe valves ??
 I have looked at their castings and instructions I have and the castings are Hexagon not round
 I thought collet chucks are for round ? And hexagon usually goes in a three jaw .
Can some one please educate me as obviously i am doing something wrong in my workshop.

Cheers
Dennis

Dennis,

You are reading WAY to much of your own personal opinion into my posts.
  I said a collet lathe is MY prefured shop tool, not in any way required to turn things round. l have been machining for 35 years. The primary advantage to a good collet lathe is the ability to take the work in and out (multiple times) of the collet and remain true. Often 3 jaw chucks will only repeat within .002 (some worse) so you have to get an indicator out.
  Point 2: you CAN hold hex stock in a ROUND collet, I do it all the time! There are 6 "points" on hex stock and 3 splits in a 5C collet, you just have to rotate the hex stock so none of the points line up with the splits in collet. I do Not recommend this for precision work as the points on brass are soft and can be deformed by to much collet clamp pressure.
Point 3: they MAKE Hex 5C collets and my last shop had a full set...picture enclosed.
Point 4: the long center stem (what the knob attaches to) is Not hex stock and many people have struggled to turn that long thin part...then when they do get it made it bends or break when they run a thread die over it. One of the solutions I saw a fellow steamer do is only turn about 1/4" at a time so your working close to the chuck, leave .0015 oversize and polish to size when long.
  The traditional way is to turn between centers. I do not yet have my Globe valve kit so after I get them and study the drawings I may do mine differently.

Good information Ben , thank you.

5C collets ?? So you need a set of square collets , a set of hex collets  and a set of round collets  then you will find something superior called ER .
 Only a 1 minute job to change chucks or collet chuck  be it 3 jaw or 4 jaw or 6 jaw or ER32

My understanding ( which maybe wrong ) is that 5C only hold on the front end ??
ER hold the whole length thus more accurate.
But then again what would I know as i am not a engineer or machinist .
I am only a Kiwi with number 8 wire attitude and think outside the box skills

Cheers
Dennis

Quote from: ShadetreeMotorcycle on February 17, 2021, 04:14:15 am

Kindly refrain from leaving WTF in threads I have started please.

I have edited it out so as not to offend the more sensitive members !!

Cheers
Dennis

Thank you!

Cheers