Quote:
Originally Posted by sanddrag
I believe a 12 tooth gear has an undercut at 20 pitch and 14.5 degree pressure angle...
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Both the 12-tooth and the 14-tooth pinions will be undercut, but the 12-tooth more severely so. From page 141 (
PDF link):
Quote:
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Originally Posted by Boston Gear catalog
On 14.5 PA gears undercutting occurs where a number of teeth is less than 32 and for 20 PA less than 18.
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The formula for the number of teeth (z) required to eliminate undercut is:
z = 2 / sin^2(a)
where a is the pressure angle. Interestingly, this isn't dependent on pitch.
I frequently summarize the core mission of FIRST as inspiring the smartest high school kids to study science and engineering, so they don't become lawyers. (It's about 70% in jest) - MikeE [more] 
24-08-2012, 08:40
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