Any problems using SKINNY 32 pitch gears...

[Andy Brockway]

Keep in mind that the stress on the gears and dogs that is most critical is the shock load from reversing. This load will be a combination from driver input and impacts on the robot. If you place the shifter in the high rpm, low torque section than you may have some shearing of the pins during shift on the fly.

Reliability is key, testing will prove your design. I suggest building now and test before the season starts. This will allow you to make changes before you need to build your new gearboxes. In 2003 we built our first dual speed in August and tested during the off-season. Several changes were implemented based on driver feedback for our 2004 design.

[sanddrag]

What material are they? I would recommend against aluminum or brass at all. Something like stainless or hardened steel will be alright in the applications listed above. I would not recommend doing the actual shifting with these gears. Keep them very near the motors in your drivetrain and they should be okay.