This is really a trig question. I have been using atn(1/6) for our standard tapered ball joint angles. All derivations and definitions of the function say it should give me the angle. It's close, but when I force a 1:6 ratio angle it results in an angle of 9.527283˚. atn(1/6) yields 9.462322˚ Can anyone explain why there is a difference? Using a calculator yields the same thing as SW. The difference is enough for our tapers not to seat correctly.
Radian/degree conversion issue?
What you have drawn is not atn(1/6). It's 2*atn(1/12), which is pretty close, but (as you have discovered) is not the same. Atn only applies to a right triangle. Yours is isosceles.
I see that we are posting essentially the same thing. LOL. great minds and all that....
good catch!
Thanks for the quick response!
That's not a right triangle.
In some instances a cut-extrude is quicker than a revolve for my tapered holes. I was using atn(1/6) for the draft angle, but see atn(1/12) is correct.
What you have drawn is not atn(1/6). It's 2*atn(1/12), which is pretty close, but (as you have discovered) is not the same. Atn only applies to a right triangle. Yours is isosceles.