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Pictured here is the stock gearbox and motor installed in a PSC Southern Pacific 4-6-0 probably from the early 90s.  Never really seen a gearbox like this before in a Steam locomotive. It is a gear tower attached worm gear.  The design is probably more common in diesels.  Seems to run OK. Wondering what people’s experiences are with this mechanism, and if there are more powerful motors of this size( 1.2” diameter and 1.75” length)? Any motor longer or wider will not fit.

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@bob2 posted:

Now that is a "C" section boiler!  Somebody should have told PSC about tender drive.  I rejected a PSC Harriman ten-wheeler for just that reason.

Which is presumably why you have scratch built your own ten wheelers😉.

There actually may be enough room in the boiler for a decent can motor if a conventional nonidler gearbox can be installed.

And here goes my ego getting in the way - all are tender drive except #2355, which has a tiny heart pump Escap motor in it - just enough power for a couple box cars and a combine (typical SP "doodlebug" consists).

I know you have seen them before, but since we love repetition of photos here . . .

2353

2355

Please don't repeat these - I am happy to reproduce them myself.

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Not a real fan of his particular drive but, I have to disagree with Bob on one thing.  When assembled there is no visible opening in the bottom of the boiler.  If you look closely at the photos you'll see what I call a belly pan.  In reality, it's the bottom of the boiler.  Everything is enclosed.  Replacing the original Pittman motor (one of their cheaper types) does help the running tremendously.  I use a similar Canon that pretty much bolts in.  Getting rid of the hideous coupling will help also.  Bob's highly recommended Toyota rubber tubing works well.  Why don't I like the original coupling?  Noisy, sloppy, wears out and gets even noisier.  I like to replace the input shaft to the gearbox and make it as long as possible.  Maybe a 1/16" from the motor shaft and install the tubing.

Jay

Last edited by Jay C

Jay,

You are right there is no visible opening to the boiler when this locomotive is assembled.  Will provide a pic of an assembled model later today.  It is really a beautiful model.  The only stock well running ten wheelers mass produced appear to be the GPM NP & C&NW types and the PRR G-5 made by Weaver, MTH, Max Gray, etc.  

Which Canon motor do you use?

Thanks for the sage advice regarding the drive shaft coupling.

Rob

I’d put that gear box and the Cannon in the garbage can, and swap in a NWSL gear box, and either a short fat 9000 series Pittman, ( if it’ll fit) or an 8000 series that’ll for sure fit,…..that gear box set up seems stupid IMO,….that’s a lot of direction swapping going on for no reason,….especially with a C sectioned boiler configuration,……are there any sub structures ( bracing) going on inside the shell?…also, a tip, when you post your pics, click on the little box that says “insert image full size”……it’ll make it easier on us old geezers,….😉

Pat

Pat,

Intuitively, I agree with you, but none of those task are not without risk of serious damage, especially in the hands of a relative novice like me.  

The wisdom of bob2 really rings true...ain’t broke, don’t fix.  If this were a sturdier piece like Weaver, Sunset, Max Gray, I would be more inclined to do the drivetrain swap.

As promised to prove Jay’s point about the boiler underside, here is an assembled PSC SP T-28.  Of course the air tanks cover the underside of the boiler for the most part. The disassembled loco pictured earlier is a drive train to a T-31.

Thanks again for all the interest and advice. Pat still haven’t how to post pics in an expanded mode, mea culpa.

Rob

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Last edited by swrr

I have done that.  I am trying to avoid making center rail comments, but I do not always succeed.

Some folks like the look of large flanges and center rails - witness the huge 3-rail scale following here.

Most folks love the appearance of these weird new sedans with the big grilles - if auto manufacturers depended on me they would go broke.  Likewise with these super detailed delicate models - my boilers are 1/16" thick, and frames are machined from 1/4"x 5/8" brass bar.  And I am really into good sand castings!

Unfortunately for me, I’m too far in center rail to turn around now,..or I would have….but even if I did, my emphasis would still be on heavy duty operations,…hence my replies to the OP,…I didn’t spend al this money to stare at them on a shelf…..just like the real roads, I made the investment, now I expect return….but as far as anybody else, again, they’re yours, do as you see fit,….I wouldn’t let a beautiful piece like that stare back at me,……Bob, as always, your work is stunning, and I stand in awe,….

Pat

@bob2 posted:

And here goes my ego getting in the way - all are tender drive except #2355, which has a tiny heart pump Escap motor in it - just enough power for a couple box cars and a combine (typical SP "doodlebug" consists).

I know you have seen them before, but since we love repetition of photos here . . .

2353

2355

Please don't repeat these - I am happy to reproduce them myself.

Bob,

I always enjoy photos of your models. I don’t mind you repeating photos of your models and I also welcome details on how you build your models.

Lee Gustafson

Thank you for the entertaining discussion.  

There really is a certain artistry and talent in machining a piece of metal into a locomotive.  Attached is picture of Locomotive Workshop frame for a 4-4-0. It was rerelease of the Lobaugh kit.  It looks it was sandcasted then machined.  The heft and the feel of the frame is impressive.   I swear if I ever have the time to build it, I doubt that I would paint it just to reveal the metal work.89DF710C-819F-4271-B8EE-8406A22D21B0

What bob2 does is remarkable.  He certainly has tried to get the word out through his numerous articles.

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