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

Builds, Repairs, Show Your Machines! => Technical Tips, Builds, and Help => Topic started by: St Paul Steam on July 01, 2019, 09:11:30 pm

Title: Jensen J-42R engine build (finished )
Post by: St Paul Steam on July 01, 2019, 09:11:30 pm: I haven't documented a new engine build in years, but with this new forum I felt I could do it here for any that want to follow along with the progress. many of you have seen the Jensen J-42 build I finished awhile back...this new engine shall be the companion engine that I had always had in mind when I built the J-42, this plant (J-42R) will have many similarities in that it will also have (2) #35 engine boilers on the single firebox, but will be different in that the cylinders will be facing outward & the axles facing inward joined by 1 flywheel, I'm going to try to mount the axles with ball bearings on this one, I see this as a challenge as the axles will need to be almost perfectly aligned & that's going to require some shimming & plenty of adjusting I imagine. this engine should be a self starter with the ability to tie the engines together & set the timing anywhere I want .
I have started on the firebox.

setup on sheet metal.
(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_133755_zpshjnxboxe.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_133755_zpshjnxboxe.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_134848_zps0qcmatcm.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_134848_zps0qcmatcm.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_154429_zpsv2j2x2zu.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_154429_zpsv2j2x2zu.jpg.html)

let the forming begin
(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_160521_zpsowhjfnkf.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_160521_zpsowhjfnkf.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_161402_zpssfxyyz9z.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_161402_zpssfxyyz9z.jpg.html)

main structure finished
(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_180336_zpsn1gfoi7l.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_180336_zpsn1gfoi7l.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_180354_zpslpmzusch.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_180354_zpslpmzusch.jpg.html)

The #35 donor engines

(https://i1189.photobucket.com/albums/z440/bruceang1/20190630_130832_zpsovv2lmps.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190630_130832_zpsovv2lmps.jpg.html)
Title: Re: Jensen J-42R engine build
Post by: IndianaRog on July 01, 2019, 09:34:37 pm: Love it...enjoyed seeing the firebox forming progression. For some reason I thought you might have had a metal break for forming the firebox base flanges...you used good old piece of steel and clamps to accomplish that...something any of us "should" be able to do.

Will follow til the steamup!!

Rog
Title: Re: Jensen J-42R engine build
Post by: Stoker on July 01, 2019, 09:44:23 pm: Oh Goodie ... this is going to be great .... Pass the popcorn please!!! ;c)
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on July 01, 2019, 10:14:41 pm: Quote from: IndianaRog on July 01, 2019, 09:34:37 pm
Love it...enjoyed seeing the firebox forming progression. For some reason I thought you might have had a metal break for forming the firebox base flanges...you used good old piece of steel and clamps to accomplish that...something any of us "should" be able to do.

Will follow til the steamup!!

Rog
I do have a small metal brake, & ironically I have been looking at a dedicated metal brakes today, I think a 12" would be big enough, they all seem to be one form or another of the same Chinese Mfg. I have decided that my Jensen collecting would focus primarily on older brass tag, black firebox Jensen's & I need better tooling for the firebox's if that's what I'm to build more of in the future.
Title: Re: Jensen J-42R engine build
Post by: CBWho on July 01, 2019, 10:37:43 pm: Get the box perfectly square isn't easy to do even with a simple box break.

Also how did you cut the nice curves for the cradles?
Title: Re: Jensen J-42R engine build
Post by: Nick on July 01, 2019, 10:54:20 pm: Thanks Again for taking the time to document this one Bruce 8)
Title: Re: Jensen J-42R engine build
Post by: Jim on July 01, 2019, 10:58:35 pm: I don't like build threads, I love them :)

Thanks Bruce for this thread :)
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on July 02, 2019, 06:08:42 am: Quote from: CBWho on July 01, 2019, 10:37:43 pm

Also how did you cut the nice curves for the cradles?
I cut them out with my scroll saw & a metal cutting blade.
Title: Re: Jensen J-42R engine build
Post by: Roscoe on July 02, 2019, 08:26:36 am: You did a real nice job with that improvised brake you have there. Neat video. Great looking fire box, nice corners.
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on July 05, 2019, 06:25:14 am: got a little farther with the build, firebox finished with several layers of paint

(https://i1189.photobucket.com/albums/z440/bruceang1/20190704_214801_zpsn5cmirur.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190704_214801_zpsn5cmirur.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190704_214826_zpsl3lt9wsy.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190704_214826_zpsl3lt9wsy.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190704_214927_zpscdokwupr.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190704_214927_zpscdokwupr.jpg.html)

axles setting in place, will have to considerably shorten them. the boilers cleaned up well enough that I don't think I'll have to send them off to be re-plated.

(https://i1189.photobucket.com/albums/z440/bruceang1/20190704_222149_zpsumkgpc86.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190704_222149_zpsumkgpc86.jpg.html)
Title: Re: Jensen J-42R engine build
Post by: Nick on July 05, 2019, 09:36:49 am: Looking good Bruce 8)
Title: Re: Jensen J-42R engine build
Post by: classixs on July 05, 2019, 10:04:06 am: Great thread Bruce, thanks for bringing us along here...

Some good progress allready, will be looking forward to follow the completion :)
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on July 07, 2019, 09:12:43 pm: I was able to make a bit more progress this weekend.

here is the cross-over manifold , it consist of 12 pieces including the pressure gauge

(https://i1189.photobucket.com/albums/z440/bruceang1/20190707_175151_zpsrrhhw1xp.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190707_175151_zpsrrhhw1xp.jpg.html)

all soldered up & ready to install

(https://i1189.photobucket.com/albums/z440/bruceang1/20190707_184435_zpsa6kqwvyo.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190707_184435_zpsa6kqwvyo.jpg.html)

test fit of some of the components, the sight gauges currently don't match, but that will be rectified soon.

(https://i1189.photobucket.com/albums/z440/bruceang1/20190707_202338_zpsucgiobvt.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190707_202338_zpsucgiobvt.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190707_202432_zpssk9v6jgc.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190707_202432_zpssk9v6jgc.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190707_202351_zpswaswydtn.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190707_202351_zpswaswydtn.jpg.html)

(https://i1189.photobucket.com/albums/z440/bruceang1/20190707_202344_zpswbuszlhj.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190707_202344_zpswbuszlhj.jpg.html)

very 1st running on compressed air.

https://youtu.be/_E6Lv2gAB4Y

the heater pan still needs to be fabricated & heaters & cord installed, then work on the plinth to do.
Title: Re: Jensen J-42R engine build
Post by: Nick on July 07, 2019, 09:46:20 pm: AWESOME Bruce!! 8) 8)

I wish these were readily available!!
Title: Re: Jensen J-42R engine build
Post by: classixs on July 08, 2019, 12:58:27 am: That sure is a great looking engine Bruce, very well done so far (https://emoji.tapatalk-cdn.com/emoji482.png)
Title: Re: Jensen J-42R engine build
Post by: Swift Fox on July 08, 2019, 04:00:42 am: Fantastic work Bruce!
Title: Re: Jensen J-42R engine build
Post by: IndianaRog on July 09, 2019, 04:49:17 pm: Love how it's coming together Bruce and thanks for sharing it step by step.

Rog
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on July 20, 2019, 07:31:52 am: I got a few more things done.

the heat shield is formed ,although I didn't seem to get any photo's of all the finished holes or paint done

(https://i1189.photobucket.com/albums/z440/bruceang1/20190713_191700_zpsnazvky0q.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190713_191700_zpsnazvky0q.jpg.html)

chimney stacks bead blasted & one of the holes taken out

(https://i1189.photobucket.com/albums/z440/bruceang1/20190714_135606_zps85q3bgjf.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190714_135606_zps85q3bgjf.jpg.html)
(https://i1189.photobucket.com/albums/z440/bruceang1/20190714_152041_zps6yoioguy.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190714_152041_zps6yoioguy.jpg.html)

heaters in place

(https://i1189.photobucket.com/albums/z440/bruceang1/20190719_205818_zpsfmbyauki.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190719_205818_zpsfmbyauki.jpg.html)

heat shield & wiring finished , quick disconnects used.

(https://i1189.photobucket.com/albums/z440/bruceang1/20190719_214910_zps0tn7raki.jpg) (http://s1189.photobucket.com/user/bruceang1/media/20190719_214910_zps0tn7raki.jpg.html)

now just waiting for the cross-over manifold to come back from the nickel platers.
Title: Re: Jensen J-42R engine build
Post by: txlabman on July 20, 2019, 04:00:25 pm: Wow!

You have been busy Bruce.

Thanks for your efforts on this build thread.

This is awesome!
Title: Re: Jensen J-42R engine build
Post by: Nick on July 20, 2019, 11:11:22 pm: Thanks Bruce, your extra steps like blanking off the hole in the stack support definitely pay off in the end 8)
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on July 21, 2019, 07:18:13 am: I spent several hours on it yesterday, replaced the split axles with a single axle...no improvement on the ease of turning over, I got is down to 3 psi before stall, I will run it in some more today (on compressed air), it seems to improve all the time as the 2 engines break into themselves. I put the cord on & tested both heaters, they work correctly & at about the same temperature on the short test I did. I finished up the plinth with a little wood putty in the voids, careful sanding & a stain of Early American with polyurethane over that once it dried (with the Sunshine we had yesterday...it didn't take long) I'm not happy with the chimney delete on the smoke stack as I can still tell where the hole was, will be re-doing that better today. now I'm just waiting for the cross-over manifold to come back from the Nickel platers (probably still a week away) & with any luck it should be finished.
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on August 12, 2019, 07:49:50 pm: I'm still waiting on the Nickel plater to get my parts done, but have been steaming it often the way it sits now & enjoying it immensely.
I performed an endurance run this weekend of my J-42R , I filled both boilers to the very top of the sight glass & ran them for 4 hrs non-stop with "on the fly" oiling every hour, this was on a homemade variac & I had it running at just above stall speed, as the water was being used up I could incrementally turn the variac down. one boiler still showed 1/8" above the bottom sight glass nut ,while the other was right even with the bottom nut, had I pushed it, I feel I could have gotten another 30-45 minutes out of it if I wanted to....but this was plenty. very pleased with this plant.

https://youtu.be/wPeUmW3e8F4
Title: Re: Jensen J-42R engine build
Post by: IndianaRog on August 12, 2019, 07:59:04 pm: Bruce, 4 hour run has got to be a record for for a standalone Jensen 35, let alone your double boiler version...wow! It sure runs silky smooth!

Rog
Title: Re: Jensen J-42R engine build
Post by: RedRyder on August 12, 2019, 08:06:35 pm: That sure does run great and looks great, too!
Title: Re: Jensen J-42R engine build
Post by: txlabman on August 13, 2019, 05:43:56 am: Excellent result Bruce.

A wonderful 4 hours of steaming....for sure.
Title: Re: Jensen J-42R engine build
Post by: St Paul Steam on August 19, 2019, 05:56:04 am: The Jensen J42R is now finished ! all the parts are now in place, & here is a rather long video of the plant, I hope you enjoyed the process & thanks for following along.

https://youtu.be/2muIcQscYwM