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True Position of feature


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I cannot figure out how to find the true position of this feature: 3343_1feb7ad62d3e94469e4688ca686016c3.jpg
3343_dac4839b07b9f114ddeaa740db62a9c4.jpg
Any way I try to get it, the MMC option never comes up.

I am very new to Calypso so I would appreciate any help!!!

Thanks.
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Can't be done. You would have to use a Symmetry plane. To the best of my knowledge,
the true position feature in Calypso will not allow that feature to be used for MMC bonus.

There is a recent post concerning this subject, with a more detailed explanation.
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Oh my! You have unleashed the kracken,Clark. Someone out there will come up with some sort of best fit workaround routine... 🤣 🤣 🤣
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.020 is quite a lot of tolerance, are you sure you need the mmc bonus to pass inspection?

If you do, there are some workarounds. You make a formula in the tolerance block of TP characteristic.

(Actual width - MMC of width) + (.020)

SPC software doesn't like that though.
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What is the criteria for getting MMC with a symmetry plane? I've never seen that work. The only features I've seen that work are circle, cylinder, and symmetry point.
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I think it will work, mmb is the total shift in the assembly. Using symmetry plane we can calculate the MMB from the MMC condition.
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It's not Symmetry, but there is a feature called Symmetry Plane. It and Symmetry Point are both features of size, so MMC/LMC will work on them.
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My apologies, I may have misspoke. So when it is used in combination
with another datum, then one of them is "un-usable" for MMC?
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B should not be used for calculating MMC because it is providing shift, not bonus tolerance.

If you draw it out, you can see that by increasing the size of A by 0.01 you would allow rotational movement of 0.07 it is not a 1 to 1 amount of bonus.

In addition to this, there are multiple holes, so due to the fact that the holes may not all be off in the same direction, in order to meet simultaneous requirement, the datum shift has to be applied the same to all 4 holes.
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Hello All,

This third time editing this post and hope the last one 😃

For second datum i test something. I create a distance between planes. And also create a symmetry plane between planes.

Then i create a cylinder and make it theoretical. For xyz use formula in the cylinder and get from symmetry plane. Also for angles and depth of the cylinder i use a formula and get from symmetry plane. Then for diameter of the cylinder i use a formula and get from distance of the planes. But i use this formula in actual diameter. For nominal diameter i put the nominal value of the distance between planes.

Then i create a position. But i choose best fit of bore pattern in position. Then i select view reference with material condition.

I attached a file how i did it. hope it is correct and works for you.

material condition.zip

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Isn't datum B useless in this case? Or almost useless?
Wouldn't |TP|.02M|A|C control the same thing?
Or it has to do something about the simultaneous requirement?

edit: OK, rethinking - |A|C| would change the design intent so it's questionable. It's the MMB on B that is useless, right?
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