If a Blueprint calls for ASME Y14.5 wouldn't this be the standard rules apply. How would I know if and when to apply ISO? I have yet to see anything on a blueprint stating this. The reason I bring this up is for the good old Profile callout. Before I make an argument, I want to cover all my resources. Customer already claims in an email that PC-DMIS is not capable of doing this. I and everyone on here already that's horse_S_H_I_T. But its Friday and I'm ready to P_I_S_S someone off
VinniUSMC Yes, I agree that the standard does not specifically tell you how to report the bi-lateral profile deviation,
and
KIRBSTER269, what you wrote does make sense, from a certain point of view. As Vinni points out your understanding is also not specified as THE way to report it.
Consider this:
Does the standard specifically tell us how to report position deviation either? Does it say to calculate the radial deviation and multiply it by two?
I just spent ~30 minutes using search terms like multiply, hyp, calculate, circular, radial, two, diametral and did a visual scan of the true position sections of the 94 standard, and did not find anything that tells us how to calculate and report the positional deviation of a hole location. (You might be able to argue that the standard
implies how it should be reported.)
Yet everyone knows that we do it by : =(SQRT(A^2+B^2))*2 (to state it as an excel formula).
Why do we report it that way? Because we know that we are dealing with a cylindrical tolerance zone and that if we dont double it, we would be reporting it as if it were a radial tolerance zone.
(Note, I was first exposed to true position at a military manufacturer 35 years ago who actually used Radial true position on their prints. I haven't seen anyone else use it since then).
Likewise, it makes sense that with a bi-lateral tolerance zone whose width is centered on a plane or line, you would relate the greatest deviation (which is either on one side or the other) back to its width tolerance zone by doubling it.
I agree with Don day of Tec-Ease. Doubling it only makes sense.
VinniUSMC Yes, I agree that the standard does not specifically tell you how to report the bi-lateral profile deviation,
and
KIRBSTER269, what you wrote does make sense, from a certain point of view. As Vinni points out your understanding is also not specified as THE way to report it.
Consider this:
Does the standard specifically tell us how to report position deviation either? Does it say to calculate the radial deviation and multiply it by two?
I just spent ~30 minutes using search terms like multiply, hyp, calculate, circular, radial, two, diametral and did a visual scan of the true position sections of the 94 standard, and did not find anything that tells us how to calculate and report the positional deviation of a hole location. (You might be able to argue that the standard
implies how it should be reported.)
Yet everyone knows that we do it by : =(SQRT(A^2+B^2))*2 (to state it as an excel formula).
Why do we report it that way? Because we know that we are dealing with a cylindrical tolerance zone and that if we dont double it, we would be reporting it as if it were a radial tolerance zone.
(Note, I was first exposed to true position at a military manufacturer 35 years ago who actually used Radial true position on their prints. I haven't seen anyone else use it since then).
Likewise, it makes sense that with a bi-lateral tolerance zone whose width is centered on a plane or line, you would relate the greatest deviation (which is either on one side or the other) back to its width tolerance zone by doubling it.
I agree with Don day of Tec-Ease. Doubling it only makes sense.
