Sticktion or is it sticksion anyway its bad starting with worm drives

[DCB]

Fitting ball bearings to control side thrust...

 

When a worm drive loco starts first the axle gear bears on the chassis side before it starts to turn causing sticktion (or the wheel bears on the chassis side, same thing)

 

Reading #brightspark 's Fighter Pilot thread I started thinking, a bad idea at he best of times, but his modified Airfix BoB with a can and 2 stage 30:1 gears was struggling with overheating on 8 bogies.

My GR Wrenn one hauls 24 with no particular issues and no evidence of overheating. It did however strip its axle gear when quite new.   That was down to really stupid design and incredibly bad workmanship, by people altering fundamentally sound Mecanno engineering to make  "Improvements which I fixed (The 2-6-4 tank gear is a direct replacement for the unavailable WC one)   However I did shim the drive gear against the insides of the chassis sides for about 5 thou side float as I do with virtually everything to improve stating and to stop the insulated axle bushes wearing away.

So it came to me. Instead of small diameter shims /washers between axle gear and chassis (or wheels and chassis)  why not drill the ends of the axle gears with a dimple to take 3 or 5 or any other number of ball bearings to bear on larger shims so the side thrust is through a rolling element,   Has anyone tried this?  I appreciate assembling this will be a fiddle but maybe not so bad as using the very small Romford axle shims I have used hitherto. 

Edited August 5, 2023 by DCB

[34theletterbetweenB&D]

On 01/08/2023 at 03:18, DCB said:

why not drill the ends of the axle gears with a dimple to take 3 or 5 or any other number of ball bearings to bear on larger shims so the side thrust is through a rolling element, 

Why not? Because what you describe will lock the axle, as you need a pair of races to bear the thrusts in both directions. A pair of regular design races with the balls or rollers running in a race frame would do the job, can see examples of miniature  items of this type in autofocus optics mechanisms.