Super easy Calypso GD&T question

[[Ro...]]

I have a program i am working on, and i have a Roundness callout that I've not used very often.

The roundness graph looks quite nice but doesn't show me my Min and Max values. It shows the points but don't show the value.

My question is that since roundness isn't a feature of size, and isn't dependent on datums, does Calypso find its middle value and the Min and Max are always equal?

For instance a Roundness of .0044 would have a Min of -.0022 and  Max of .0022?

I know Flatness does this, so I'm guessing Roundness is the same.

[[To...]]

yes, it is the same.  the computed circle or plane is based the center of the min and max point, so it will always be equal deviation.

[[Ky...]]

Just to add to what Tom said (which is correct), you can reference this document on the standard fitting algorithms in CALYPSO. Specifically you want to look at "Minimum Feature"
https://portal.zeiss.com/knowledge-base?id=420544

[[Ma...]]

In accordance with standards, the default setting for roundness evaluation is "Minimum Feature" or Chebyshev fit, but you can change it to any of the other fits to suit your specific needs.

 

Edited April 1, 2025
clarity