gears vs chain

[JohnHudak]

Hi All, I'm in the planning stages of an 1 1/2" Scale EMD model 40, 4 wheeled switcher..... I've looked over all the chassis designs out there for the Davenports, Plymouths, and other little switchers both commercially built, and scratch built... And I've noticed that some are using motors between the wheels, connected to the axles with gears, while other motors are mounted to the frame with a short chain to a "jackshaft" then longer chains from there to the axles....
Can anyone comment on your preference? I can probably fit either way on my planned chassis, but I just want to find out if one way might be better than the other....
Thanks; John

[fresnojay]

John, I am building a Super Huskie and have been told that the chain drive is much more forgiving in case of a derailment. Both work equally as well but heard in a derailment that the gear are prone to stripping as the chain and sprocket setup gives preventing any stripping. I would think in absolute worst case you pop a link in the chain drive setup which is easier to repair than a stripped gear. Plus the chain setup is much more tolerant of dirt and track conditions. But I am choosing to go chain drive for ease of repair and upkeep.

Jason

[SteveM]

I'm using train drive, but I have three axles, each one sprung. Driving all three axles from one motor was easiest with chain drive.

I'm driving the center axle from the jackshaft and then one chain each to the front and rear axles.

Check out http://www.surpluscenter.com for chains and sprockets. Nice selection and great prices.

Steve

[Fender]

I used chain drive on my Davenport critter. Right now I'm experimenting with plastic chain between the motor and jackshaft to reduce noise, and results are incomplete. Avoid overkill on the chain size. Probably #25 steel chain is plenty big unless you are building an SD-45 or something.

[JohnHudak]

Right now I'm experimenting with plastic chain between the motor and jackshaft to reduce noise, and results are incomplete.

Thanks Dan, I guess I wasn't even considering the noise factor.. Just how noisy are chain drives?
John

[Fender]

John,
My existing chain drive is noisy, especially when coasting. This is because the motor is high rpm, and my sprockets are too small, and the chain speed too high for steel chain. I can't do much about the motor besides replacing it, but I am changing to larger sprockets and chain (both plastic), which should be quieter. For example, the motor sprocket was 9-tooth and the jackshaft was 18-tooth. I'm changing these to 15-tooth and 30 tooth. Also may need a better way of adjusting the chain tension. Note that the final drive to the axles will remain steel chain and sprockets. Will see what happens.

[Fender]

I was working on the chain drive last night, but when I finished assembling it, discovered the batteries were dead. So the charger is on today, and maybe I can run a test tonight.

[Ironflyer]

Hi John,
I will try to get some pictures from the side and under of a locomotive that I finished that someone else started. They built four GP40's with 8 horse Kohlers, and Eaton pump and motors in each truck..a good thousand pounds each. One of them can easily walk away with 20 people,.....with toothed belts and cogs...smooth, quiet, strong, with an easy way to keep in proper tension with a simple idler. They've run at least six years in that kind of service.
I know you could take it from there with no problem.
I'll get some pics this weekend at the meet.

Sorry you guys aren't coming back out,

Paul

[JohnHudak]

Thanks Dan, Let us know how it turns out....
Paul, I thought about timing belts and pulleys first, but I read somewhere not to use them (it might have been in this forum?) So I looked elsewhere.... I guess we can now throw them into this equation??
We wish we can come up for the meet, but our travel "budget" is all used up for the year.....
John

[Ironflyer]

Hello John,
Heck, I wouldn't rule them out at all.
I'll show you what is under those beasts. An electirc driven two axle for a couple of passengers to ride behind wouldn't tax it.

My travel budget is toast too.

So I'm making parts instead.

Paul

[Fender]

John,
I ran the Davenport and it still is noiser than I want. I didn't order enough of the plastic chain, so will need to get some more. This thing has two jackshafts and I replaced the chain going to the first one, but need to get another foot or so to replace the steel chain going to the second jackshaft.

[fresnojay]

I had a chance to run a little electric similar to what my husie is a couple monthes back and it didn't seem to noisy. But then again I am a rookie at this. It there a trick to making it quiet? Lube, proper or appropriate gear/sproket size?

Jason