Position of non-holes

[[Da...]]

So far I have only ever done position with hole features, so I am stuck on this one.
The .244 is the width of a nub that sticks out from the end of a shaft. I have it measuring the top and bottom of the nub to get the width, but I cannot figure out how to do the position callout. I am understanding this as the position of the entire nub feature, but I cannot figure out how to tell Calypso that. I tried doing a symmetry line between the top and bottom so I could get the center of the feature, then seeing how far that is off from center. But I don't know if that is enough, and I don't know how to get an actual position dimension.

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[[To...]]

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Try creating a Symmetry Plane, not a Symmetry construction of 2 planes. Open Features > Special Geometries > Symmetry Plane. Open the Symmetry Plane, take a bunch of points on both sides. Correct your nominal values. Tick Distance checkbox, enter tolerance. In strategy window, place a Clearance Data between the last point of first side and first point on second side. When you close the feature, click NO, when asked about automatically adding clearance data.

Next, create a position. Change it to a Best Fit Bore Pattern. Select Datum A for your Primary, enter your tolerance. Then, select the Symmetry Plane. In best fit area, un-tick Translation checkbox, leave Rotation checked.

I think that's everything.....

[[Ky...]]

Hello Darci,

As best as I can tell with that print, it seems like we want the symmetry between the two sides there. If you want to use MMC, though, you will want to make sure you use the "symmetry plane" feature in features>special geometries. If you recall the points from both sides in there, it should be able to put into a true position without too much issue and then put in the MMC as normal (though, even if we can't get MMC turned on in Calypso, that I don't think would be too difficult to do via formulas).

Strictly speaking, though, I think the best way to do something like this is via profile since, at least in the ASME standard, I believe true positions of non-circular features imply a "boundary" calculation (so you are making sure that the boundary doesn't cross a certain boundary based on the datums and size of the feature), but that isn't always practical, and people sometimes get weirded out if you show profile instead of TP.

Here is a knowledge base that sort of covers a similar item. Hopefully it will be of help:
https://portal.zeiss.com/knowledge-base?id=863300