[Me...] Posted November 5, 2019 Share Posted November 5, 2019 First off, thank you for taking the time to read this and forgive me if I seem uneducated. A drawing I have has a "Profile of a line" callout (0.15Max) on a 10mm diameter. At first I'm thinking this is roundness but I believe "Profile of a line" uses a perfect line and has a tolerance area around this perfect line when roundness is a maximum deviation. The book I have says "profile of a line" is a location type tolerance and "roundness" is a form tolerance. (GeoTol Pro by Scott & Al Neumann). Normal, this is easy with using the Profile characteristics but I do not have the curve license. Thanks again for reading. Link to comment Share on other sites More sharing options...
[sh...] Posted November 5, 2019 Share Posted November 5, 2019 Can you supply a photo or hand drawn sketch what you're looking at? Link to comment Share on other sites More sharing options...
[Me...] Posted November 5, 2019 Author Share Posted November 5, 2019 Does this help? Link to comment Share on other sites More sharing options...
[sh...] Posted November 5, 2019 Share Posted November 5, 2019 just check the profile exactly at the theoretical diameter of 10MM In my mind a form tolerance like roundness would be a better callout. But after all I would check it using the profile of a line as the print states. Link to comment Share on other sites More sharing options...
[Me...] Posted November 5, 2019 Author Share Posted November 5, 2019 Thank you! Link to comment Share on other sites More sharing options...
[Br...] Posted November 5, 2019 Share Posted November 5, 2019 This controls form AND size. If it were only roundness then there would also need to be a size tolerance associated with the 10mm diameter. In fact, if the Ø10 had a normal ± limit tolerance to it instead of the Line profile, it would be awfully similar as the size controls form as well. So what you have here is a TRUE PROFILE at exactly Ø10mm. You then have a boundary of 0.15 equally disposed on both sides of this true profile. Now because this is a profile of a line tolerance, it exists at every cross section through this feature, whereas a Profile of a Surface tolerance would have a more 3D tolerance zone with two boundaries that all of the surfaces must fall within. Your drawing may be showing that the profile only exists at one cross section though by the looks of it. Another way you could sort of look at it for the sake of simplicity, is Ø10±0.15 Link to comment Share on other sites More sharing options...
[Er...] Posted November 5, 2019 Share Posted November 5, 2019 Ø10±0.075 Link to comment Share on other sites More sharing options...
[Br...] Posted November 5, 2019 Share Posted November 5, 2019 Please sign in to view this quote. It's a diameter so you have 0.075 on both sides. It can be 10.15-9.85. Link to comment Share on other sites More sharing options...
[Er...] Posted November 5, 2019 Share Posted November 5, 2019 Haha I stand corrected! Your ofcoure right. I've been sick for a long time, I blame my bad luck when thinking on that 😃 Link to comment Share on other sites More sharing options...
[An...] Posted November 6, 2019 Share Posted November 6, 2019 Transforming a Plus/Minus-Tolerance into a Profil-Tolerance. See attached.Contribution_06_11_2019.pdf Link to comment Share on other sites More sharing options...
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