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Unread 02-05-2016, 13:18
BoilerMentor BoilerMentor is offline
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Re: pic: The worst of the stripped VexPro gears

Cbale2000 posted about it, so I guess it's my turn.

Personally, I'd like to see us really understand the failure, because maybe as a community we can help VexPro understand the issue and solve what, at this point, is not a uncommon problem. This presents an opportunity to show VexPro what we need what the bounds of our use case are.

As a supplier, at some level, the needs of the customer and the use case for the component need to be considered. I'm not suggesting that didn't happen, but I am suggesting that multiple, multiple failures indicate there's a problem, likely worthy of a fix.

I'm all for teams taking accountability when they use COTS components improperly, but using a gearbox designed to be a part of an FRC drive train in an FRC drive train isn't something to apologize for or be shy about in terms of customer service situations.

If what a number of folks are saying is true, why isn't there a specification for strength provided, like the shaft torque spec on the AM PG series gearmotors? I know the idea that a product needs to stand up to every possible use case is silly, but none of the reported failures have been that far outside the realm of what I would consider typical use for a gear box in FRC.

I'm still of the opinion that angular misalignment has to be related to these failures. It drastically reduces the apparent face width of the gear and as a result can initiate failures. Coupled with such a brittle material there's no reasonable expectation that the gear would survive. The question then becomes, what is the source of the misalignment.

As a bonus, here's a handy reference:

http://www.faculty.fairfield.edu/wdo...othLoads04.pdf
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