GDT guys, I need help with this callout.

[[Ch...]]

Can someone smarter than me tell me if this is a legit callout. If it is not, how?

[[He...]]

Yes it is legit. It could be instead of a simple perpendicularity but it can also be part of a simultaneous requirement depending on the rest of the drawing.

2 good videos:
https://www.youtube.com/watch?v=V46bUBmlS-g
https://www.youtube.com/watch?v=4VG0bsdYVF4

[[Ch...]]

Ok,
i've seen this with patterns and prints that have simultaneous requirements. But it is weird to me that this is the only feature to use that DRF.


So how do I construct this without using perpendicularity in Calypso?

[[Br...]]

Henrik is right. As unnecessary as it seems in this application, a position tolerance controls Location and orientation of features of size. So In this case, because datum feature A cannot constrain any translational degrees of freedom significant to effect the location of Datum Feature B, all it can do is control the orientation. Effectively, this specific tolerance has the exact same tolerance zone as a perpendicularity tolerance would have. But like Henrik mentioned, the only difference is that it could be subject to a simultaneous requirement. Although it seems odd to me that anything else would in fact be located to a DRF [A], rather than [A|B].

[[Br...]]

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You could do a few things. You might test them out to see what works. You could do a Position tolerance to AB. You could see if you could just do a position tolerance with only A plugged in for that matter and see if it works. You can even do a best fit bolt pattern where you best fit the translational degrees of freedom on a single feature. Do a Perp tolerance too just to see which one you get the same numbers from.

[[Ch...]]

I wanted to use AB, but the feature called out is datum B in my interpretation. Correct?



Tried just constructing it in the position tolerance and no dice.

Same with the best fit bore pattern. No Dice.

[[De...]]

If you use Datum A for your primary then use Datum B as your secondary in a regular true position.

Yes B is not actually in the callout, but so long as you make sure B is constrained to A when you make it primary it will align to A correctly and then locate based on B (while it is aligned to A) - the result is it only checking orientation of B to A

[[Br...]]

I had a minute to test it out. If you just do a regular position tolerance and only put datum A in as the primary datum feature leaving secondary and tertiary blank, you should get the exact same results as a perpendicularity tolerance.

[[An...]]

See attached.

Contribution_04_12_2019_a.pdf

[[Wi...]]

Should just be perp