Reversing electric engines

[Si]

I asked this elsewhere, but didn't get an answer (probably because it was in a fairly obscure thread) so thought that I'd try here...

I intend to put a switch on the underside of the AnDel battery powered chassis of my loco, so that I can automatically stop and start it by having 'arms' that come up out of the track and hit the switch as it goes past. This, I believe would be fine for stopping and starting but what about reversing? If it's going along forwards and I switch it straight to reverse without stopping it first, am I likely to damage the motor or gears?

If it makes any difference, it has a 3v motor running off a 1.5v battery to get the speed fairly slow, and it won't be pulling very long trains, perhaps four wagons at most.

thanks!

[tuppenced]

Si,
Over the last century many commercial models have had on-off and reversing switches actuated by lineside gear. Some clockwork, some electric - and of course London Transport used the trip-cocks on full-size live steam (though not for reversing!)

No, you won't damage anything unless your gears are very flimsy.

You've not mentioned the type of gearing, but I would guess you have plastic worm-and-wheel gears in mind. These will stop your engine dead almost as soon as the current stops, so o reversing there's little or not extra inertia compared with starting from a stand.
If you have this type of gear-set, GET SPARES ANYWAY when you build your model, and put a dirt guard under them.

You can modify commercial toggle switches to make them more suitable. If you shorten the spring a little you'll reduce the change-over resistance. If you have a lathe you can substitute a different arm.

David

[Si]

Many thanks David.