Car and Locomotive Shop diesel tower gear box

[Jay Criswell]

Mike,

No worries.

Since our last back & forth I've bounced between probably a dozen projects (maybe more) and actually finished one. That gives me one for the year.

Jay

[pitogo]

I give up on trying to find the original motors and gear for the CLS gearbox and decided to go my own route with 3D printed parts. I printed drive cups, used 4mm shafts and 4mmx8mm ball bearings with 16Tooth timing pulley and a 100 tooth belt.

I printed three belt drive towers before I got the last version pictured, mainly the holes are smaller than what is drawn up in my modeling software, so if its an 8mm bore I needed to make it 8.25mm to fit the ball bearings. It's printed with PLA+ which I find surprisingly strong, we'll see. There are probably stronger materials ABS, PETG, PPA-CF, Nylon etc each have different tradeoffs. I don't have a mill or a lathe to I print what I need.

[up148]

Nice job Mike! This 3D printing is a game changer.

I have a friend who bought a C&LS 4-10-2 pilot model that wasn't powered from Henry's estate. He thought he could find a motor and gearbox on the open market, but that never happened. Apparently Henry didn't have spare parts or drives. After a couple of years of looking he sent it to Gary Shrader to be powered.

[pitogo]

Thanks Butch.

Another not so pleasant surprise, the fans and housing are all gone too. If you need a visual see this https://youtu.be/We4_qJab0Og?si=R7-t2_cdyOJiqm1_

Missing fans and housing


Missing fans and housing


Printed my own with .2mm nozzle, it looks better than it shows through the grills. It won't be as good as the original made of brass, the non functioning version looks good, this is the bottom side so not as nice as the topside. Will save photos of the business end when this model gets painted.


For now I'm happy to have it running. The gear motor works pretty smooth. I'll have to see how it works in the long run. I can always print spare parts and/or use stronger filaments, PLA+ is medium strength.

[R.K. Maroon]

Michael -- I am impressed by your ability to crank out the replacement fan housing. I do a bit of 3D modeling and printing and would consider such a multi-component assembly as a major project. I wouldn't be so impressed if I knew you did CAD work all day as part of your job, but I know you don't, so...kudos to you.

As to the transfer tower for the Trainmaster, are you using the printed material for the shaft bearings? I would not have been so brave, but maybe that's my old-school thinking getting in the way of a new and better idea. I did note your comment that if it doesn't work out you can try a different material. That way of thinking is how progress is made, but, being happily stuck in the past, I would have designed it to accommodate ball bearings.

Jim

[up148]

I don't do any printing, although my son does, but it almost like magic. You guys are amazing.

[riogrande491]

Nice job, Michael. I'm impressed.

I stumbled across several old interior photos of a Reading unit.

For some reason Henry used two Pittman motors. He personally told me that he used 24 Volt motors "so that the engines would really feel the grades." Curiously, when I measured a couple of his motors in RS-11s the rotor resistance was about 10 ohms, for a stall current about 1.2A. That does not match 8x14 Pittman data sheets for any of the stock windings. I'm guessing the motors were not actually 24V but wound for something much higher, which would partially explain why they produced so little torque. I just noticed the labels still on the motors and wish I had taken a peek to see what the label revealed.



I put this unit back on the shelf when I realized what a huge project it would be to replace all the incandescent lighting and install DCC sound.

There were 5 micrometers for the fans and what looked like a home-etched PCB with circuitry to sequence the fans according to track voltage. I have no clue how the motors came on in sequential pairs with only two wires going to them. The PCB contained three 3-terminal ICs and a bridge rectifier, along with a few passive components and single diodes.

[pitogo]

Hi Bob,

Thank you for posting those photos. It's nice to see what the model actually looks like complete. I did a test run at DFW O Scale Club and it ran great on plain DC. The photos are of prototype gearboxes and drive cups using PLA just something cobbled up fast. I printed final versions which are much finer in both PETG and PLA-CF. Wow PLA-CF is pretty strong. The drive itself is very quiet, nearly silent creeping, but the gearmotor I used is quite loud at top speed. A high quality gearbox could be an upgrade in the future but for now she's no longer a static model. Since it's a gearmotor it's got lots of low end torque so going extremely slow is not an issue. I plan to put DCC and will replace all the bulbs with nano SMD Led 0402 LEDs. The scheme will be Reading.

[pitogo]

As to the transfer tower for the Trainmaster, are you using the printed material for the shaft bearings?
Jim

Where possible I always try to use ball bearings. Yes the transfer tower are using 4mm x 8mm x 3mmball bearings for the shafts. Here's a printed version using PLA-CF. Tolerances are much better 8.1mm for a nice press fit.

[pitogo]

Originally, I was looking for the C&LS motors and gear, unfortunately this was much harder to find. Thanks to the recommendation from Jay, I able to source a motor that is capable and powerful. I used an inexpensive $14 gearmotor from Amazon to POC the project. With that success I went to look for a 3.71:1 gear motor from Faulhaber. I've used Faulhaber motors in other projects and know they are quite powerful for their size, reliable and quiet. I modeled a mount and printed the final version from PETG-HF, with the other components in the tower belt drive and drive cups printed from PLA-CF and annealed for 8 hours.

[up148]

Absolutely stunning work Mike....congratulations!

[pitogo]

Wow, this thing starts moving at 0.6v and smoothens at .8 to 1.0. I've also tested it at 12v and it really moves along. Mechanically she's done, next up DCC and then off to paint.

https://youtu.be/m1lYvIOrPhk?si=FvLoG6UqHZpkn3Hc