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Unread 07-01-2016, 10:38
BoilerMentor BoilerMentor is offline
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Re: Sonic Shifter - recent feedback?

Quote:
Originally Posted by aldaeron View Post
I agree with Chris - why not just run the numbers yourself instead of guessing? Here is a great presentation on shear stress in a spur gear. Matweb should have material info on 7075 aluminum and 4140 steel (not sure how to apply allowance for the ceramic coating on the aluminum gears). See what safety factor your teeth have for each gear in the gear train for each material. The less robust the mounting, the more safety factor is needed.

-matto-
The ceramic coating is going to mostly effect wear characteristics that might otherwise be problematic in aluminum. Running the numbers is without question the way to make the decision. Ideally if you had the resources and time, you'd validate those calculations with actual load testing. I wish Machinery's would donate a copy to each FRC team. It'd make the world a better place.
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