Evaluation methods on print

[[Mi...]]

Say I want something inspected by another party, and want to make sure that a circle is to be evaluated constrained in XY, or is measured using max inscribed or min circumscribed, etc.

I think usually these things are done at the discretion of the QA inspector's judgment, but is there an ASTM standard for defining these things on a print?

[[Ch...]]

Believe it or not, I recommend the default print out for this.

[[De...]]

I have not heard of a ASTM/ASME standard that covers this.

I believe that ISO 14405-1 defines the options we can see in Calypso for diameter sizes. As shown below.

The different ISO options are the GG, GC, GN, GX, etc. shown in the picture.

[[SH...]]

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I have not seen evaluation method strictly stressed in the print, it might say unless otherwise specified follow this standard, such as asme y14.5,iso 1101, iso 2768, DIN standard or JIS standard etc...

Due to the rapid development in the CMM measuring technology, it might come in future...

[[De...]]

I didn't think of it but I guess I should have stated that according to ASME Y14.5-2009 features of size are all supposed to conform to rule #1 (envelope principal) which means that form is a function of size.

Therefore according to Y14.5-2009 the actual local size of all features of size should fall with the limits of size.

Essentially what I am trying my best to say here is that though it may be hard to measure a given feature of size to exhaustively cover all the requirements of Rule #1 in ASME Y14.5-2009 it does in fact specify what requirements a feature of size must meet in order to be in tolerance.

As for constraints, if it is a feature being measured in a characteristic with a DRF then Y14.5 also gives rules for how the part should be constrained based on the Datum Reference Frame.

As for defining how to measure it to cover all of whats required that part is still up to the person measuring the part, but the standard does define what is supposed to be covered by the check.

Usually the problem is not an inability to completely measure the part but in determining how extensive checks must be in order to check the part good enough without going overboard.

In my opinion some type of defined method would be nice so different inspectors would always be making an 'apples to apples' comparison, however this will only ever work if the people drawing the prints bother to learn the meanings and apply them correctly.