[Exla357]

We've had a very similar problem with our choo-choo mechanism.

We have a bag motor on a 250:1 reduction and our problem has been that the orbital gears inside the box, somewhere, have been shattering. The box still functions (as the pieces of the gears are held in place by friction) but there is a skipping motion as well as some wierd noises. We had to replace it twice in the 3 days before bag day. I would suggest opening up the VersaPlanetary and checking it out.

Also, make sure you've got a hard stop on your catapult that ISN'T the choo-choo. This causes incredible torquing and can eventually break the whole assembly. We use a steel cable.