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True Position of a Slot + MMC


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Hello all, I was wondering if there was a way to add the MMC bonus tolerance to the True Position of a slot. Here is the print callout and the dialogue box from Calypso:
2084_ee18902bdfd4df0dd6c4faa3a5fb24d7.png
2084_5f13d09db5416c58d591c89fb79f9e14.png
Thanks,

Zach
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Some people recall the measured points into a circle, or something like that. I'm wondering how you are fitting the resolved geometry of a slot into a cylindrical tolerance zone?
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If it were bi-lateral true position you could use a symmetry plane
constructed from the long sides of the slot, if there were enough
material to measure a plane.That would allow you to use MMC,
but with diametric true position I don't think MMC is possible.
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I ended up taking the cylinder from each side of the slot and recalling them both into a circle and going that route (Things look great in my result file). I'm not really worried about the part being bad, but I'm curious why the slot TP can't use the MMC callout (My GD&T and Calypso knowledge are novice at best).
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For one, it isn't a regular feature of size.

Also, the resolved geometry of the slot is not cylindrical (or an axis) so it can't be put into a cylindrical zone. The slot has a length and a width (two widths). Each width should be positioned separately in a planar tolerance zone. This would allow MMC.

You're looking at a print error/poor application of GD&T.
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Perfect, thank you for the explanation. I'll have to go back and sure up the program with symmetry planes.

Thank you everybody for your help!
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Jacob is right. There shouldn't be a diameter symbol in the FCF. The tolerance zone is a boundary in the shape of the elongated hole. To really do the slot at MMC you need to create another slot that has nominals that represent the virtual condition of this slot. So it would be an 8.1 X 11.2 slot in your case. Youll need to convert this slot into a 2D curve via the "creating features" window. Then recall the points from your measured slot into this curve. Then you can do a unilateral profile tolerance to make sure it doesnt violate the inner boundary.

clear as mud?
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