[To...] Posted November 3, 2021 Share Posted November 3, 2021 Hello everyone. Looking for suggestions on best method to report position on the slot below. This one is throwing me off a bit due to basic slot length Datum Feature A is plane on bottom Datum Feature B is plane on right end Datum Feature C is plane, perpendicular to view. TIASlot Position.jpg Link to comment Share on other sites More sharing options...
[Ro...] Posted November 3, 2021 Share Posted November 3, 2021 I would treat it the same as a slot with rectangular coordinates and report each axis separately to the same tolerances in the FCF. Normally there will be a separate callout for each axis, but since there isn't, it's a linear tolerance zone, and it's position and not profile, I don't think you have another choice. I guess you could report just the one direction that's shown and let the drawing notes/tolerances control the slot length and position. You'd either need a note with some sort of catch-all, like profile .xxx to A-B-C or something similar, or something like a general tolerance document that controls undimensioned features with a table of sizes and corresponding tolerances, similar to a hole chart. The slot length, even though it has a basic, has no tolerance directly applied to it, so it's kind of a judgement call on whether to use the FCF or some other controlling method. Link to comment Share on other sites More sharing options...
[Ma...] Posted November 3, 2021 Share Posted November 3, 2021 True position controls controls only the location of the slot center. Slot width has a dimensional tolerance. Slot length is basic and is not controlled in snippet shown. Link to comment Share on other sites More sharing options...
[To...] Posted November 3, 2021 Author Share Posted November 3, 2021 Please sign in to view this quote. I agree but then that brings up the question, "what is the tolerance on the length of the slot?" There are a few "questionable" gd&t concepts on this drawing.... including a note regarding ANSI Y14.5, which leads me to think this might be a drawing from the early days.... Link to comment Share on other sites More sharing options...
[Da...] Posted November 3, 2021 Share Posted November 3, 2021 I agree but then that brings up the question, "what is the tolerance on the length of the slot?" There are a few "questionable" gd&t concepts on this drawing.... including a note regarding ANSI Y14.5, which leads me to think this might be a drawing from the early days.... [/quote] That is odd. Normally there is a note or an all over profile to control basics. Link to comment Share on other sites More sharing options...
[Cl...] Posted November 3, 2021 Share Posted November 3, 2021 Please sign in to view this quote. Would the .390 Basic default to the UOS Block tolerance? There are a few "questionable" gd&t concepts on this drawing.... including a note regarding ANSI Y14.5, which leads me to think this might be a drawing from the early days.... [/quote] That is odd. Normally there is a note or an all over profile to control basics. [/quote] Link to comment Share on other sites More sharing options...
[Da...] Posted November 3, 2021 Share Posted November 3, 2021 Please sign in to view this quote. That is odd. Normally there is a note or an all over profile to control basics. [/quote] [/quote] That is my understanding. Link to comment Share on other sites More sharing options...
[Ro...] Posted November 3, 2021 Share Posted November 3, 2021 Please sign in to view this quote. Negative. A basic dimension has no tolerance and is a theoretical perfect nominal. Features defined by basic dimensions derive their tolerances from the FCF. Link to comment Share on other sites More sharing options...
[Cl...] Posted November 4, 2021 Share Posted November 4, 2021 Please sign in to view this quote. That's embarrassing, I knew that and completely forgot. Link to comment Share on other sites More sharing options...
[Da...] Posted November 4, 2021 Share Posted November 4, 2021 [img][/img] An "All Over" profile controls basic dimensions. Link to comment Share on other sites More sharing options...
[To...] Posted November 4, 2021 Author Share Posted November 4, 2021 Please sign in to view this quote. There is no Profile callout on drawing. Link to comment Share on other sites More sharing options...
[To...] Posted November 4, 2021 Author Share Posted November 4, 2021 Please sign in to view this quote. How would you deal with the MMC? Link to comment Share on other sites More sharing options...
[Ro...] Posted November 4, 2021 Share Posted November 4, 2021 Symmetry planes, symmetry points, or the old circle construction method to get the MMC. Maybe at a couple of depths, depending on the depth of the slot. Link to comment Share on other sites More sharing options...
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