pic: Another stripped VexPro gear

[Michael Hill]

Originally Posted by ollien

I was considering buying vex gearboxes for next season, but with stories like this I'm not so sure...

With 8" wheels, people aren't quite taking into account sudden shocks that can be imposed on gears with the torque of 2-3 CIMs in a gearbox. Start doing some Lewis Gear equations and use a decent factor of safety. Vex gearboxes weren't meant to do certain things, and as a designer, you need to determine whether the gearboxes can handle the loads you're putting them through. If they can't, you have two choices: find another gearbox or modify the COTS gearbox to make it work.

[techhelpbb]

Originally Posted by Michael Hill

If they can't, you have two choices: find another gearbox or modify the COTS gearbox to make it work.

I think the Vex box is actually pretty nice but:

If your team bought this COTS and managed to avoid buying the broach and press for it and you need to make a modification a few hundred bucks could really hurt. On the flip side of that you could buy extra gears early but first you would need to foresee the issue and then be able to source them...it looks like late in the season the supply chain got tight.

I rarely mind helping and I bet at CMP you might get the machine shop to broach steel gears you might buy just in case: but this could really hurt at competitions less equipped and might be pointless if you did not get suitable steel gears before you need them.

So really it is a design issue, but those 20 tooth steel gears I sent to CMP were AndyMark products broached. There are steel gears you can order on Amazon that could be broached (take longer to get).

BTW recognition to BeardyMentor and Philip for helping me out on this.