How to Find Profile

[[Da...]]

Until recently, I have not seen many drawings with a profile callout. The ones that did have it were just one specific feature. 

Lately we have been getting a lot of new parts that have something like this as the only type of tolerance on the weldment or any of the components.

I barely understand what this means, let alone how to check it. 

I only have Calypso...no curve or freeform or anything like that.

All I can think is that I have to fully probe each individual surface and feature and make a profile dimension for each of them...but that isn't right either, is it? Because don't they have to all tie together somehow so it is the profile of the complete part?

Also, CMM inspections on welded parts are not done during production. So the people welding want to know +/- target and I was told to just spit it in half (so +/- .060 in this case) but I don't know if that is actually correct. 

 

[[DW...]]

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 You are correct, this note is becoming much more common on engineered drawings. Usually it is something like, "Unless otherwise specified all features must have a surface profile within XXX". This is the author's catch-all note to control 100% of the part geometry. Unless you are using a CT (X-ray) or scanner based system, you cannot reasonably perform this measurement. Where I work, we do have a CT based system, and when I actually do select ALL of the surfaces and evaluate the profile (usually to itself), the results tend to surprise the customer because for the first time ever someone is checking this note in its entirety. 

Edited 8 hours ago

[[Da...]]

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Since you are online at the moment, can I ask you another question?

What does the composite tolerance mean? I am not very familiar with them either, and I am even more confused since there is no datum.

 

[[St...]]

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Hello Darci, for composite/Multiple Single Segment position, I recommend reviewing Faro.com's and GDandTbasics.com's material on this topic.

I haven't seen them without datums however, so I can't help with that. Sorry!

[[Ke...]]

https://www.gdandtbasics.com/composite-position-vs-multiple-single-segment-tolerances/

I'm pretty sure ASME requires at least 1 datum for position. For example, a cylinder with a position to the bottim surface plane would essentially be an evaluation of perpendicularity.

[[Ky...]]

For the profile, it would depend a bit on the part itself. You can do surface profiles (most) standard geometries, though there is a bit of a trick to it with the old GD&T engine (see https://portal.zeiss.com/knowledge-base?id=868503). Additionally, you can do it with individual points, but it is significantly harder (see https://portal.zeiss.com/knowledge-base?id=2495545).