[Me...] Posted July 9, 2020 Share Posted July 9, 2020 I'm looking for either the section in ASME that covers this question and/or your thoughts on the best way to tolerance this... Let's say I have a pattern of holes that are a datum feature. Each of those holes in turn has a slot centered to each hole individually in the pattern. Although the slots are a pattern, so to speak, each slot feature needs to be independently located to the hole it surrounds. What is the correct method to tolerance this? I've seen callouts that tolerance the slots and reference the datum pattern with a note like.... 8 plcs, individually or something similar, but I'm unsure if there is a specific way to tolerance this or if it's interpretive. Thanks all for any feedback you can provide, Robert Link to comment Share on other sites More sharing options...
[Da...] Posted July 9, 2020 Share Posted July 9, 2020 So you want to locate to individual hole or to pattern of holes? I have a hard time to visualise. Can you sketch something please? Link to comment Share on other sites More sharing options...
[Ia...] Posted July 9, 2020 Share Posted July 9, 2020 I believe this is what you're looking for. ASME Y14.5-2018. Section 10.4.8 has more info. Link to comment Share on other sites More sharing options...
[Me...] Posted July 9, 2020 Author Share Posted July 9, 2020 Perfect! Thanks so much, Ian! I only have up to ASME Y14.5-2009. Link to comment Share on other sites More sharing options...
[Br...] Posted July 9, 2020 Share Posted July 9, 2020 Please sign in to view this quote. The same concept can be found in the 2009 standard. Look for section 7.4.8, and Figure 7-37 Link to comment Share on other sites More sharing options...
[Me...] Posted July 9, 2020 Author Share Posted July 9, 2020 There it is. Thanks, Brett. Link to comment Share on other sites More sharing options...
[An...] Posted July 10, 2020 Share Posted July 10, 2020 See attached.Pic_7-37_a.pdf Link to comment Share on other sites More sharing options...
[Ia...] Posted July 10, 2020 Share Posted July 10, 2020 Please sign in to view this quote. Andreas, you should really start stating you're concerns/questions as opposed to just throwing question marks on things. I know you have a great understanding of GD&T, so I have no clue what doesn't make sense to you. It would also help not-so-familiar forum members (including myself) follow along better. Link to comment Share on other sites More sharing options...
[An...] Posted July 10, 2020 Share Posted July 10, 2020 Please sign in to view this quote. Still hoping to get some feedback from people who are willing to think in an unconventional way. Far beyond the paragraphs of the ASME. See attached!Pic_7-37_d.pdf Link to comment Share on other sites More sharing options...
[An...] Posted July 11, 2020 Share Posted July 11, 2020 The orientation of a pattern - only one dimension required. See attached.Pic_7-37_e.pdf Link to comment Share on other sites More sharing options...
[An...] Posted July 13, 2020 Share Posted July 13, 2020 How to dimension a pattern. Principle: as much as necessary See attached. (E.o.T.)Pic_7-37_f.pdf Link to comment Share on other sites More sharing options...
[Aa...] Posted July 13, 2020 Share Posted July 13, 2020 Here's my interpretation of what's going on in 7-37 of 2009: The lower "segment"which is not really a segment, because it's a separate Feature Control Frame and not a PLTZF controlis intended to ensure that each mating component will fit without interference into the larger hole and the four surrounding holes. It's a clearance requirement. Hence the MMC applied to the tolerance and the MMB applied to the datum D reference. They put down 6x for the lower FCF because that's the control that ties each pattern of surrounding holes to its corresponding central datum hole. I haven't the foggiest notion of a functional requirement that might be addressed by the upper FCF. Your "Pic. #1": I have no idea where this example came from, because you didn't give your customary reference. However, this is a completely different situation, because in this case the "6x" refers to a pattern of six features instead of six patterns of features and is intended to means 6x for both the upper and lower FCF. Again, this is not a composite FCF but two different FCFs because they each have their own position symbol. The diameter symbol preceding the tolerance amount indicates the shape of the tolerance zone for each feature as it always does in ASME (as well as ISO). Link to comment Share on other sites More sharing options...
[Da...] Posted July 13, 2020 Share Posted July 13, 2020 Please sign in to view this quote. I visualized this as a gauge panel. The upper FCF functions to control the orientation of the hole pattern - without it, it would not matter how the holes were clocked. Y Link to comment Share on other sites More sharing options...
[Aa...] Posted July 13, 2020 Share Posted July 13, 2020 Please sign in to view this quote. Thanks! That makes sense. That would be a straight-forward way to ensure the mounting brackets don't interfere. Link to comment Share on other sites More sharing options...
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