Thomas1911's Shay Project

Thomas1911 · February 15, 2013, 02:29:15 PM

I mentioned in my layout thread a while back that I was starting on a Shay project. Well, here it is....

While perusing the web one day, I came across a site detailing the different types of geared steam locomotives. On the page covering the Willamettes, I found the following picture of a design that was apparently on Willamette's drawing boards when they went out of business. A two-truck, 6-axle locomotive.

http://www.mrollins.com/willam.html

Thinking what an interesting model this would make, I immediately started wondering what it would take to turn a Bachmann Shay into this never-built locomotive. Some initial studying and measuring of the Bachmann model lead to the conclusion that it was feasible, but I decided that since this isn't really a prototypical locomotive, I would save some headache and not try to turn the Shay into a Willamette. Building the proper cylinder bank and valve gear didn't seem very appealing.

My original plan was to turn this into a "Pacific Coast" –style Shay with the all-weather cab, girder frame, and cast trucks. After much thought, I decided I didn't want to tackle trying to scratch-build the cast truck side-frames. This decision lead to the next decision that making the frame and cab modifications would be pointless without the cast truck frames. I decided I would only worry about necessary changes to fit the 3-axle trucks, leaving the factory truss-rod frame, boiler, and cab. Modifications needed would be the front and rear pilots and water tank / fuel bunker. Maybe in the future I'll come up with a way to make the cast truck side-frames, and then make the other modifications.

The physical part of the project started with extra front and middle Shay trucks that I had in my workbench drawer. I began disassembling them and taking measurements of all the components. I then started drawing the components in AutoCAD to determine how certain components were going to fit together and what would need to be modified. For simplicity sake and compactness, I decided to not model the truck equalizer bolster as seen in the Willamette design. Instead, I would utilize two factory middle trucks and graft on an articulating 3rd axle and frame cut from the other trucks. I worked out the pivot point and designed the needed parts for the articulating 3rd axle in CAD.

With design work done, I began by modifying the extra trucks. Only minor trimming needed to be done to the middle truck. The front truck saw considerable cutting and splicing of the side-frames to form the single-axle unit. Next, pivot parts were cut from styrene and a bushing from brass tubing, then the parts were glued (with CA) to the appropriate truck component. Holes were drilled (and tapped) after the glue had dried. Lineshafts were reassembled with NWSL gears and one of the original slip-joints cut down to the appropriate length to go between the 2nd and 3rd axles. This makes up the front 3-axle truck.

I didn't want to spend money on another Shay until I was surer this truck was going to work. So, with the first truck done and appearing to function as expected, I was confident enough to make a purchase. During the planning and design process, I had been keeping an eye out on eBay for a suitable Shay. After a few months of watching, I was lucky enough to score the particular model I was looking for at an acceptable price, an undecorated steel cab model.

Before any serious or irreversible damage was done to the new Shay, I wanted to test the first trucks operation under its own power before proceeding any further. This meant disassembling most of the locomotive and removal of the front pilot for the new truck to fit. Testing went well. Only issue that arose was that the shortened slip-joint would come apart while negotiating left-hand curves. The truck would want to articulate instead of rotating in relation to the frame. I solved this by adding a travel limiter to the 3rd axle frame. I also added some weight to the 3rd axle frame to help it track a bit better.

As seen in the pictures the front pilot will need to be extended forward about 7/8" to clear the 3rd axle. I may look into the possibility of moving the front bolster rearward to reduce the amount needed to extend the pilot.

Currently, work is beginning on the rear truck. Once it is complete, will move on to extending the front and rear pilots and figuring out what to do with the water tank & coal bunker.

More to follow.....

Doneldon · February 15, 2013, 04:29:04 PM

Thomas-

This looks like an interesting project being done well. I congratulate you.

As to extending the front of the loco, I wouldn't worry about how that might look.
Articulated steam engines all have huge front porches and yours would be no
different. In fact, it just might be the feature which best attracts eyes to the
locomotive. People will realize right away that they are looking at something
unique.

-- D

WoundedBear · February 15, 2013, 06:00:45 PM

Outstanding!

Sid

Thomas1911 · February 15, 2013, 07:48:30 PM

Thank you for the compliments.

D,
I wasn't to concerned with the looks of the "front porch". In fact, I thnk it would look fine. I expect it would have been an excellent place for the crews to transport frequenly used tools, rigging equipment, etc.

However, I have just realized that pushing the coupler too far out from the bolster may lead to some derailment issues in curved sections of track. Going to have to do some checking on this. Probably won't be a problem with normal rolling stock. Cars where the couplers run relatively close to the centerline of the track, like disconnect trucks, may be a problem though.

Doneldon · February 16, 2013, 03:42:01 AM

Quote from: Thomas1911 on February 15, 2013, 07:48:30 PM
Thank you for the compliments.
However, I have just realized that pushing the coupler too far out from the bolster may lead to some derailment issues in curved sections of track.

Thomas-

You're welcome. You earned the praise.

You can let your whole draft gear pivot which should help a bit with the coupler misalignment problem on curves.

-- D

jward · February 16, 2013, 09:17:37 AM

what about mounting the pilot on the front truck similar to a mallet? that would solve the swivel problem. normally i don't recommend truck mounted couplers, but you should have enough weight on the front truck to minimize any problems.

Geared Steam · February 16, 2013, 12:03:32 PM

Very interesting project, I will be watching this thread with much interest

Thomas1911 · February 16, 2013, 01:02:21 PM

Thanks for the ideas on the coupler problem. I'm going to make some temporary mounts for the front pilot and see just how much of a problem I really have.

Jeff, mounting the pilot to the truck is a possibility I hadn't considered. Thanks.

Did make a little progress modifying the side-frames for the rear truck last night.

Thomas1911 · February 21, 2013, 12:00:19 PM

Finished modifications for the rear truck last night. Went a lot faster second time around.

I don't have a decoder for this yet, so testing has been limited to a short, back and forth runs on a section of track with an old power pack. It has run well with the amount of testing thus far.

Now on to extending the frame.

Doneldon · February 21, 2013, 02:39:21 PM

1911-

I've been thinking about your project a little. If you are still having problems with the drive shafts pulling out of their receivers on the front and rear mini-trucks, you can just make the sockets a little deeper. If that interferes with turning, cut out small amounts of the pockets on both sides of both pockets so the drive shafts have a little more clearance but not so much that they can pop out. Making the cut outs just a hair larger than the drive shafts but smaller than the head of the drive shaft should do the job.
-- D

Thomas1911 · February 22, 2013, 01:34:07 AM

D,
Thanks for the suggestion, though I think the issue is pretty much taken care of with the travel stops I added. I left the sockets as long as I could, but still collapse enough to make an 18"R curve. With the slip-joints being so short, it doesn't leave much in the way of travel. Then add in the loose fit....things have to be just right.

I'm sure some final fine-tuning will be needed, but I think its going to work out alright.

Now just to get some extended test runs in.

ryeguyisme · February 23, 2013, 10:21:27 AM

it's killing me how really cool this is, I mean TRULY this is an amazing idea

Thomas1911 · February 23, 2013, 01:46:21 PM

Thanks Rye. This design was different enough and by having the extra parts, just couldn't resist trying.

It's too bad Willamette didn't get a chance to build the design. Or Lima could have incorporated it into their Shays, though I imagine patent restrictions were probably the reason they didn't.

ryeguyisme · February 23, 2013, 01:58:49 PM

All you really have to do is maybe put a bigger/longer boiler on there and make a bigger fuel bunker, the third "tender" fuel bunker shell might be big enough for your needs

http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_92&products_id=1645

Thomas1911 · February 23, 2013, 05:10:32 PM

I wasn't going to do anything with the boiler, just extend the front pilot to clear the truck. The original water tender frame will be spliced on to the rear of the main frame. Then the water tender body and coal bunker will be spliced together in some form or another. Haven't decided exactly how to go about this yet.

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Thomas1911's Shay Project