Thread: Gear Face Width
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Unread 05-08-2014, 12:39
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Re: Gear Face Width

Quote:
Originally Posted by Andrew Lawrence View Post
All VP/WCP gears are .5 total width, but a .375 face width. This is because of the two .0625 thick nubs on either end of the gear.
This is only true for gears above 24 teeth. Pinions and gears under 24T from Vex are .475 face width, with just a .0125" nub on either side to get the total width to .500".

As for the OP's question about gear strength, if no one gets to it I'll answer that in a day or two, but someone smarter will probably beat me to it. A good first order approximation is to use Lewis numbers and model gears as cantilevered beams.

With regard to making gears, unless you want a different diametrical pitch (e.g. coarser teeth for an arm gear) you're probably better off just doubling the number of Vex gears on the shaft to double the effective face width. Very hard to speak in generalities here; it depends on the mechanism.
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