Jump to content
Private Messaging is activated - check "How to" on how to disable it ×

Improper GD&T


---
 Share

Recommended Posts

Yes, I know this is not a valid GD&T callout but what GD&T characteristics could be used in place of this?  They're basically saying the if the part get thinner, the flatness tolerance will grow.  I'd like to hear any ideas using valid GD&T characteristics.  Currently, the vendor uses a gage to slide the part thru but looking for a cmm check to put a number on it.

Screenshot 2025-02-04 160908.jpg

Edited
Link to comment
Share on other sites

This is a very interesting question, Tom. I am a little hesitant to give any real ideas since, as you said, it isn't standardized and heaven knows what it actually means, but hypothetically, we are checking to make sure the symmetry plane lies within that tolerance zone? That is the symmetry plane, right?

 

I was initially thinking that maybe we could use true position to do it, but true position doesn't really reflect the "point" nature of flatness after a little more thinking.... Maybe it would be as simple as just doing a profile of the symmetry plane with a formula in the tolerance to calculate the bonus tolerance? I would say flatness, but you can't put a symmetry plane in for that....

Link to comment
Share on other sites

This isn't a valid callout? I just opened up 14.5-2009 and figure 5-9 describes derived median plane flatness with MMC.

Link to comment
Share on other sites

Please sign in to view this quote.

My bad.  However, I am not able to select a symmetry plane in the standard flatness characteristic, nor can I apply MMC to a symmetry plane in the GDT Flatness in the Beta Engine.  So, now my request changes from "Improper GD&T" to "How do I in Calypso?"...lol

Edited
Link to comment
Share on other sites

I have an older Calypso so i don't have that new GD&T - so for me it would be symmetry of planes, which can be placed there and then formula into tolerance as Kyle stated.

And as stated i would rather preffer surface profile.

Link to comment
Share on other sites

Well scratch my nonsences above 😄

Only thing i was able to think of would be set of symmetry points and then recalled into one plane. This will report some deviations.

Link to comment
Share on other sites

I dont know if its a good solution, but since you cant apply a flatness to a symmetry plane, you can make your own and apply flatness with a formula tolerance for the bonus

Edit: Martin beat me to the same idea by a few minutes

Screenshot 2025-02-05 072430.png

Edited
Link to comment
Share on other sites

Please sign in to view this quote.

I saw somewhere on the web about recalling symmetry plane into another symmetry plane to allow some calculation. I'm unsure if it's about that, but worth a try.

Link to comment
Share on other sites

 Share

×
×
  • Create New...