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Unread 21-11-2016, 19:04
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asid61 asid61 is offline
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Re: 775pro .5" Hex Output Shaft

Quote:
Originally Posted by Sam Skoglund View Post
Thanks for the input! It looks like I should either drill better holes in hex shaft, or use the 32DP gears. Does anyone know of a 5mm bore 5mm HTD pulley?

The reason I am doing this instead of a versaplanetary gearbox is because last year we had issues with shredding the weak little gears in the versaplanetary. Will the 12 tooth 32DP pinion gear from WCD hold up to high pressure is there are a few other stages after it in the gearbox? Or if it is a high stress mechanism, should I try to use the hex shaft adapter method instead?
Because the 775pro is a high-speed low-torque motor, even when stalled it shouldn't break a 32 pitch gear. I calculated an approximate tooth force of 17lbs, and a tooth strength of 72lbs according to this calculator: http://www.botlanta.org/converters/dale-calc/gear.html so you have a pretty large factor of safety there.

Of all the failure modes I have seen from a VP, shredding gears is not one of them. That doesn't mean it's never happened, but you should make sure you used the correct planet and sun gears on the right carrier plate.
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Last edited by asid61 : 21-11-2016 at 20:03.
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