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General Surface Profile Callout

We have had a difference of opinion here at the shop that I work at and I'd like to get the opinion of some people that have been in this field for a while, because I know there are people out there that have a better understanding of GD&T than I do.
Let's say you have a CAD part model with a general profile tolerance ("Unless otherwise specified, all part features are subject to a surface profile tolerance zone of .020 with respect to the primary datum A, secondary datum B, and the tertiary datum C") and a specified thickness tolerance of +/-.010. You have a wall on this part that the model clearly shows does not have a constant thickness from one side to the other. Do you tolerance both sides of the wall according to the general profile tolerance, or do you hold one side to the general profile tolerance and then the other side to the thickness callout in spite of the fact that the thickness is not constant? Obviously if you hold both sides to the general profile tolerance, you have a potential for the thickness to run as high as +.020 if both sides of the wall were at top tolerance, but I don't see how you can hold it to a thickness tolerance when you don't have a constant thickness to hold.

Opinions? If you can back up your opinion with a specific aspect of the GD&T standard instead of "here's what I think" that would be even better...
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  • What kind of part, stamped or milled?

    If it is a stamped part (sheet metal), one side is "master" (even though CAD is master, one side is more master than the other, re the stock thickness tolerance).

    The only time I've seen this in a model is for extrustions. The 'master' side of the CAD model is the side that the extrusion punch is on, since it determines the 'straight' wall, the other side of stock 'thins' due to the forming process. So, the 'punch' side of stock is profile 0.020


    We primarily deal with milled parts. I've never dealt with punched parts. We do have some parts that are cut from extrusions, but they usually go through milling operations.
Reply
  • What kind of part, stamped or milled?

    If it is a stamped part (sheet metal), one side is "master" (even though CAD is master, one side is more master than the other, re the stock thickness tolerance).

    The only time I've seen this in a model is for extrustions. The 'master' side of the CAD model is the side that the extrusion punch is on, since it determines the 'straight' wall, the other side of stock 'thins' due to the forming process. So, the 'punch' side of stock is profile 0.020


    We primarily deal with milled parts. I've never dealt with punched parts. We do have some parts that are cut from extrusions, but they usually go through milling operations.
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