[Answer42]

Originally Posted by magnets

I agree with the mecanum wheel issue. There's two ways these things fail. The rollers come loose, and the plastic wheel itself shatters. I broke a 6 inch one dropping it on the floor.

One more question for the vex guys, why is the slot in the dog shifting shaft so long? It's significantly longer than the travel of the cylinder.

You'll find that's the case for most dog shifting gearboxes you can buy. I would assume it just makes the whole setup more tolerant inaccurate cylinder placement. Although I'd be curious to hear what the reasoning is from vex.