Gear boxes

[PenrithBeacon]

AFAIK all model railway gearboxes employ a worm and worm wheel as part of the reduction design, but bevel gears are more efficient. 

 

Has anybody converted, say, a Branchlines or High Level gearbox to using bevel gears and could they say how they did it using which components, please

Cheers

[DCB]

One of the problems with Bevels is they are prone to stripping if the load becomes excessive, I tried Scalextric crown wheel and pinion but they kept stripping as I couldn't stop the shafts getting out of line, make the bevel geras chunky enough to survive and you get a notchy transmission.   I will be watching this thread with interest.

[newbryford]

15 minutes ago, PenrithBeacon said:

AFAIK all model railway gearboxes employ a worm and worm wheel as part of the reduction design, but bevel gears are more efficient. 

 

Has anybody converted, say, a Branchlines or High Level gearbox to using bevel gears and could they say how they did it using which components, please

Cheers

 

Not quite all.

Portescap RG4 gearboxes use bevel gears.

Although relatively rare - they are still available on the second-hand market

 

The "replacement" SG4 uses crossed helical worms that are far more efficient that the normal single start worm gears used

 

 

 

 

[-missy-]

Hello.

I have played around with the design of gearboxes using bevel gears. The biggest problem I had was trying to achieve a decent reduction in the gear ratio, it's where a worm and wheel have a distinct advantage. Of course with a worm and wheel the ratio is much better but you cannot back drive through them as you can with bevel gears.

M.

[34theletterbetweenB&D]

Anyone with enough experience of global RTR model railway product to identify manufacturers who have replaced the worm with alternatives for 'turning' the drive? The prevalence of the worm isn't an accident, and now that most manufacturers seem to have grasped that as small a diameter as possible is good, it is probably near optimised for our purposes.