[Me...] Posted August 3, 2020 Share Posted August 3, 2020 I know we've went through this before from previous posts but I need some refreshing... Our customer gave us their interpretation for the .002 to A composite tolerance and it was their understanding that the lower segment was solely focused on Orientation (Parallel to -A-) only. Is this true to the standard or does .002 profile to -A- also effect the .700 flange width? Link to comment Share on other sites More sharing options...
[Cl...] Posted August 3, 2020 Share Posted August 3, 2020 I don't see which surfaces are the datum's? Link to comment Share on other sites More sharing options...
[Me...] Posted August 3, 2020 Author Share Posted August 3, 2020 I'm sorry Clarke, Datum A is the face to the right on that .700 width basic. -B- is an OD & -C- is an on-center locating dowel bore on the -A- face. Link to comment Share on other sites More sharing options...
[Cl...] Posted August 3, 2020 Share Posted August 3, 2020 "Is this true to the standard or does .002 profile to -A- also effect the .700 flange width?" I am no expert, but this is my interpretation. Link to comment Share on other sites More sharing options...
[Ri...] Posted August 3, 2020 Share Posted August 3, 2020 Your top tier is already controlling this. The bottom tier is only controlling the orientation. Link to comment Share on other sites More sharing options...
[Cl...] Posted August 3, 2020 Share Posted August 3, 2020 Please sign in to view this quote. Ok, so by orientation you mean parallelism? Link to comment Share on other sites More sharing options...
[Ri...] Posted August 3, 2020 Share Posted August 3, 2020 Please sign in to view this quote. In this case, yes. Link to comment Share on other sites More sharing options...
[Me...] Posted August 3, 2020 Author Share Posted August 3, 2020 This is the only thing that I can find in the 2009 standard about it...Seems relevant save for the "Pattern" part. Capture.PNG Link to comment Share on other sites More sharing options...
[Br...] Posted August 3, 2020 Share Posted August 3, 2020 Y14.5-2009 para.8.6.1.1 says: "...Datum referencing in the upper segment of a composite profile feature control frame serves to locate the profile locating tolerance zone relative to specified datums. See Fig. 8-19. Datum referencing in the lower segment serves to establish the limits of size, form, and orientation of the profile feature, relative to the datums specified." Notice location is left out. So Size form and orientation are controlled by the lower segment of a composite profile tolerance with a single profile(ie not a pattern). Because your feature is a planar feature, there is no size to control. So basically like everyone has said, since it is only controling Form and Orientation to Datum A, Its essentially a parallelism tolerance. (I'm assuming its nominally parallel to Datum Feature A.) Link to comment Share on other sites More sharing options...
[Mi...] Posted August 3, 2020 Share Posted August 3, 2020 Please sign in to view this quote. Sorta off-topic, but how does that work for a reference frame? You're saying -B- and -C- are concentric, right? Link to comment Share on other sites More sharing options...
[An...] Posted August 4, 2020 Share Posted August 4, 2020 See attached.Pic_8-21_a.pdf Link to comment Share on other sites More sharing options...
[Me...] Posted August 4, 2020 Author Share Posted August 4, 2020 Please sign in to view this quote. Just to play devil's advocate here, It does say "limits of size"....Would the .700 basic dimension be a limit of size or a location from -A-? Link to comment Share on other sites More sharing options...
[Br...] Posted August 4, 2020 Share Posted August 4, 2020 Please sign in to view this quote. Its referring to a profile that has a closed contour shape. So in the Figure you posted you see a pattern of features that have a closed contour. In those cases their size is controlled as well because the profile tolerance zone does not change shape, but rather its allowed to shift. the 2018 standard has even introduced a new modifier for a dynamic profile that does actually expand or contract. In those cases the limits of size would not be controlled. Link to comment Share on other sites More sharing options...
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