05-20-2017, 11:46 AM
There is an easy way to check a gears pressure angle:
Pressure angle is the flank angle of the rack that the gear engages with so we need a rack to measure - take some child's Plasticine or modelling clay - form a long flat surface and roll the gear on it to make a nice impression. With a very sharp knife and ruler cut the clay along the formed rack so that you can look at it's profile sideways. With a school transparent protractor you can easily see the difference between 20 PA and 14.5 PA
Pressure angle is the flank angle of the rack that the gear engages with so we need a rack to measure - take some child's Plasticine or modelling clay - form a long flat surface and roll the gear on it to make a nice impression. With a very sharp knife and ruler cut the clay along the formed rack so that you can look at it's profile sideways. With a school transparent protractor you can easily see the difference between 20 PA and 14.5 PA
Andrew Mawson, proud to be a member of MetalworkingFun Forum since Oct 2013.