Boston & Maine B15 2-6-0 Scratchbuild

[narrowminded]

As far as for inside bearings, remember that every gearbox or steam chassis ever made depends on them.  It's all about the quality of the bearing material vs. the shaft material.   There may be more marginal friction, but good material and workmanship will eliminate a lot of it.

In all of your experience, what combination of axle and bearing materials have you found best suitable for pickup.  Did that also include some form of sprung wheel or axle wiper? 

[garethashenden]

I have been sent some pictures to share with you of a similar locomotive built in 2mm Finescale. It was built by Tim Watson and has so far covered more than 150 miles on Copenhagen Fields. Built by Baldwin for the Great Northern (UK) in the 1890s.

Prototype







This engine, like mine, has the valve gear inside of the frames. Tim, being the craftsman that he is made it work.


The gearbox and rear axle



Cylinders and pistons



Frames

[mmagliaro]

That... is.. some... mighty fine work there.   The engineering of the gearbox, the valve slider, the delicate detail
work all over that thing.  That's a 1st class job.  Woo hoo!

[peteski]

I love the thin rod (steel) drive shaft and ball bearings on the worm (Victor would be proud)!

[Chris333]

Wish I could do that in O scale 

[garethashenden]

I'm still procrastinating on making tender wheels, but I have managed to get some work done.

It's quite easy with a locomotive with leading but not trailing wheels to end up with a center of gravity forward of the driving wheels. This is particularly common with 4-4-0s, and to a lesser extent with 2-6-0s. We want our locomotives to be as heavy as possible, so we fill all available space with lead/tungsten/whatever.  There are gears above one driving axle, and it's nice to have an open cab, so the weight ends up toward the front of the engine. Then the whole thing tips forward slightly and spins it's wheels.

The easiest solution is to put weight in the tender and get the tender to transfer most of it's weight to the back of the locomotive. To do this the tender body and frame as separate. The body is mounted on a strip of metal. This is in turn mounted to the frame via a pivot 2/3 to 3/4 the way back along the tender. The front end of the strip is then formed into the drawbar and connected to the engine.

All of this is well illustrated in the first post of this thread: http://www.rmweb.co.uk/community/index.php?/topic/101551-lnwr-super-d-in-2mm-finescale/

I had always been planning on doing this, but I wasn't entirely sure how to do it. I had previously made two separate trucks, but I had trouble figuring out how to attach them. What I eventually decided on was a rigid frame for the tender. It's quite a short tender, so radii should be a problem.



With the body perched on top:

[Joetrain59]

Nice work! Did the B15's have rear, tender mount lights?
 Thanks,
 Joe D

[eagle5473]

Not sure where you are but there is at least 1 real one still around in Connecticut

http://www.danbury.org/drm/1455.htm

[Joetrain59]

That Mogul at DRM is 10 mins away from me! There only one time, for a car show. Have to go back, but now I'm thinking there was no rear light.
 Thanks,
 Joe D

[chicken45]

Amazing!

[garethashenden]

Nice work! Did the B15's have rear, tender mount lights?
 Thanks,
 Joe D

There is a rear light. It's not at the very end, about where the coal rails end, in front of the water filler.

[Joetrain59]

I'll have to mosey on over there. Any particular pics anyone wants me to take? When car show was there, kids all over that staircase, and in engine cab.
 What did W.C.Fields utter about kids in a movie??? LOL.
 Thanks,
 Joe D

[garethashenden]

Well, after umm, three years  , there has been progress!!!

I spent three years procrastinating on making wheels. I bought a lathe and made a couple, but they weren’t very good and then I got distracted. Then I bought an Alco S3 from Lee with a couple of cracked gears. I ordered replacements from NWSL, and while I was poking around the site I noticed they sold 33” N scale wheels without axles. So I bought 10.
I mounted 8 on half axles and put them under the tender. Then I made a drawbar and a bunch of other little things and the motor is now connected to the gearbox! There aren’t any shorts, so it should run, but I have to go to work now so I won’t get to find out for sure until I get home.

Here are the pictures.

[peteski]

Nice to see you back on this project, but remind me: why didn't you use the standard low-friction pointy axle tender wheels riding in bearing cups in the sideframes?

[randgust]

Do you have a gearhead on that motor in the tender?   

My 'go to' combination on my own 2-6-0 was a Kato 12v. 11-105 motor and a Gizmoszone gearhead on the front.   Similar mount though, used NWSL universals and shafting.   Mine only had 48" drivers and is smaller.   

When Chris built his logging 2-6-2 (Jerry DeBene has it now) I don't know if he used a gearhead or not in his tender drive, but it sure ran well.  At that time we were using Faulhaber motors from Motorman (RIP).   I tried several motor and gearhead combinations in my tender including a Faulhaber 0816, Max's Mashima, and my own 1105+gearhead custom blend, it easily won. 

That frame is still one sweet piece of work there.