Large Scale Central

Sources for gears for custom drives?

Modeling
#1

I am building a 2-8-0 with Hartland wheels, the axels are 0.24". I would like a gear ratio of about 1:30 or even 1:40.

I have found these: [ulr]http://cambrianmodels.co.uk/16intropage2.html[/url] in the UK, but the axel holes are too small.

Recommendations please!

Thanks,
Alec

#2

Alec:

How did you measure or determine that the axle diameter is .24"?

Unless you used a micrometer or caliper to arrive at the .24", I would guess that the axles are actually 6mm in diameter. 6mm is 0.236".

You just need to have someone (perhaps the supplier?) bore the gears to 6mm. Best done on a lathe as it will be lots more accurate than using a drill press.

Those are common dimensions and a common thing to do in your part of the world.

Hope this helps.

Happy RRing,

Jerry

#3

http://www.nwsl.com/

#4

http://www.smallparts.com/s?savedSearchKeyword=&keywords=&page=1&size=20&searchNodeID=16412201&ref_=sp_sc_4_2_lf&x=0&y=114

#5

Try Barrys Big Trains? Barry Olsen posts ehre…he’d be the one for a custom drive…might already have something acceptable for your project…

#6

Thanks all!
Jerry, I measured the axel with some cheap digital calipers, they do not go all the way to thousands of an inch… I will check, but you are probably right saying it should be 6mm.

I can probably find someone to bore the holes out for me locally.

David, thanks, it looks like they had more range than I thought!

Mik, Good website, I will have a better look later.

Bart, A BBT product would be fantastic and last forever, but it is way over budget. I figured that if I make something myself, I can learn from my mistakes and make it better next time- still saving money.

Alec

#7

Alec,

W.M. Berg at http://www.wmberg.com/

Stock Drive Products / Sterling Instruments at http://www.sdp-si.com/

Also have a large selections of small gears and chain drives.

Bob C.

#8

Bob, a great selection there, thanks for sharing these.

Alec

#9

Alec,

I’ll try to be brief, Bob Cope has given you my source for gears: Stock Drive. But a little tip, buy plastic gears with brass hubs. If not plan on cross drilling plastic gears for a ss pin through the axle. Also plan on using a double thread worm which will prevent surging. The cardinal rule is that the driving gear is harder (material) than the driven gear. I follow all of this and more; haven’t had a gear failure in more than 12 years.

Barry - BBT

#10

Barry,

My preference in all cases for small drives is to us a steel driver and brass driven (whenever the sizes are available).

Bob C.

#11

Thanks Barry and Bob for your advice,

Barry I will try and look for a double thread worm on the site Bob posted. I want to avoid potential surging, but my grades are smallish, so hopefully it shouldn’t be a problem…

Alec

#12

What exactly causes surging, anyway?