MMC bonus on a non-feature of size

[[Ti...]]

Zeiss inspect will not let you use MMC for a position check on a non-feature of size. For example, let's say a print calls out a diameter or distance from theoretical sharp corners(TSC), basically the size is some fake diam or distance that is not attached to the real part(see picture).

I don't use Calypso, but I'm curious how you all would handle this in that software before I ask for this as a feature request again, it would be nice to say how it is done in calypso and pcdmis.  In pcdmis, we can create two opposing points and construct a circle from these points to get a diameter or distance that can be applied towards a position check with MMC bonus.

I've tried this numerous times in Zeiss Inspect/GOM and no matter what I do I cannot get the MMC bonus to flow thru into the actual check. At one point I created a curve > circle from curve > back to curve > back to circle and it looked like it was working, but it doesn't flow the bonus thru into the results.

[[Cl...]]

What picture?

[[Ti...]]

Opps sorry...there are many non-feature of sizes you can dream, but this is one a co-worker just asked me why I didn't apply MMC to it.

I can apply MMC though in GOM, I just have to use the user defined area, create a bonus variable, create the center pnt/plane location, then do the math of making sure that the bonus variable plus the stated tolerance is larger than 2x the deviation of the mishit.

[[Pe...]]

You can recall the intersection's xyz into two theoretical points, and then set the vector of those points to aim outwards.  Then you can recall them into a symmetry point which does allow for MMC.

[[Ti...]]

Thanks for the reply, interested to hear if there are any other methods you all use.  I mentioned this above, but in pcdmis we would create a midpoint from the two intersection points. Then construct a circle using the midpoint as the center and either int point as the radius value.  I've tried this exact approach in Zeiss Inspect/GOM and it looks like it works, but it will not allow you to pass along the size of this feature(constructed circle) into the position check. 

Edited November 19

[[Ma...]]

Here is one method

https://cmm-quarterly.squarespace.com/calypso-free-training/calypso-true-position-of-a-slot-with-mmc-formulas

[[Ti...]]

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 I'm not familiar enough with calypso to understand that workflow, I've never even seen the software. How you could create a circle from two planes is weird to me...I could actually follow this workflow in  pcdmis b/c planes in pcdmis also creates a centroid point so you can theoretically create a circle from the midpoint of both planes mid point, and then use one of the centroids as the radial value, but that is not needed....b/c the two planes is a feature of size.  I know that this is just an exercise in how to get this done, but I could not follow that workflow at all.  Does calypso create a definitive centroid point from a plane so you can derive a point from a plane?

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 workflow made perfect sense in that you establish a symmetry point(mid point) and two opposing vector directional values and points...that is basically the workflow in pcdmis.  In case anyone from GOM reads this thread that is my preferred method to create a size feature from a weird non-feature of size to apply MMC to a positional check. 

Edited November 20

[[Ch...]]

symmetry plane ??

[[Ma...]]

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So, the key is to make a perpendicular line (normal) between the walls of the slot. From here you get the mid-point along that perpendicular line. Then follow the formulas to finish the circle.