[Mi...] Posted August 16, 2018 Share Posted August 16, 2018 Not really a Calypso issue but.......... I have a part here that is called out as 0.8 +/- 0.02. So 1.00mm max. Also has a flatness call out of 0.25. I have Eng's here saying that they can use the 0.25 and add it to the 0.8 tolerance to help in sorting these parts for thickness. Some might be over the 1.00 mm. I know profile callout can play a role but a flatness callout? Im not so sure about this but I cant find any ref material to fight them. Still looking Thoughts? Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/ Share on other sites More sharing options...
[Mi...] Posted August 16, 2018 Share Posted August 16, 2018 You may look at Rule #1 2.7.1 Limits of size control the form of the feature in ASME Y14.5 Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116002 Share on other sites More sharing options...
[Ri...] Posted August 16, 2018 Share Posted August 16, 2018 It seems pretty clear. If the out of flatness makes the parts greater than 1.00 mm thick, they are out of spec. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116004 Share on other sites More sharing options...
[Ri...] Posted August 16, 2018 Share Posted August 16, 2018 In section 5.4.2 it states the Flatness tolerance must be less then the size tolerance unless there is an Independency Symbol attached to the size. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116006 Share on other sites More sharing options...
[Aa...] Posted August 16, 2018 Share Posted August 16, 2018 Not often I get to say this, but the engineers are right. See 5.4.2.1 and 5.4.1.2. The wider form tolerance overrides the envelope rule. The independency symbol is not required in this case. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116008 Share on other sites More sharing options...
[Pe...] Posted August 16, 2018 Share Posted August 16, 2018 Mike, if the nominal is 0.8 and the tolerance is +/- 0.02, then the max is 0.82, not 1.00. Did you accidentally type an extra zero, or am I missing something? Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116010 Share on other sites More sharing options...
[Aa...] Posted August 17, 2018 Share Posted August 17, 2018 Please sign in to view this quote. I should clarify that: It's not just because the form tolerance is "wider". The application of flatness in this case "widens" the size envelope by the flatness tolerance. So, if the size is really 0.8 +/-0.2 (max 1.00) and the flatness tolerance is 0.25, then it must fit within an envelope of 1.25. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116012 Share on other sites More sharing options...
[Ja...] Posted August 17, 2018 Share Posted August 17, 2018 The way that I interpret 5.4.2 is that flatness must be less than the size tolerance. If the independency symbol is used than the flatness tolerance may be greater than the size tolerance. So, I think there should be an independecy symbol on the print or else the flatness must be with the size. If the size tolerance is +/-.2 then you have .4 that you can fit .25 flatness within. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116014 Share on other sites More sharing options...
[Pe...] Posted August 17, 2018 Share Posted August 17, 2018 Is the flatness callout on a single plane (either on a leader or extension line directed to a single surface) or on a feature of size (attached to the size dimension)? Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116016 Share on other sites More sharing options...
[Aa...] Posted August 17, 2018 Share Posted August 17, 2018 Please sign in to view this quote. If you look at the sections I referenced, they're pretty clear, especially if you look at the figures they reference. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116018 Share on other sites More sharing options...
[Jo...] Posted August 17, 2018 Share Posted August 17, 2018 Please sign in to view this quote. This is actually important. If the flatness is called out with a leader line directed at a surface then the value cannot be more than the size tolerance. If the callout is associated with the size dimension then the callout is fine and the value is added to the MMC size of the part to determine the outer boundary. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116020 Share on other sites More sharing options...
[Aa...] Posted August 17, 2018 Share Posted August 17, 2018 You're absolutely right, John. I assumed the flatness was applied to the derived median plane, not the surface. If it's applied to the surface, it does not override the envelope rule, and 5.4.2.1 does not apply. Thanks for moderating. 😉 Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116022 Share on other sites More sharing options...
[To...] Posted August 17, 2018 Share Posted August 17, 2018 Please sign in to view this quote. I was trying to stay out of it. 🤣 🤣 Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116024 Share on other sites More sharing options...
[Mi...] Posted August 17, 2018 Author Share Posted August 17, 2018 Snippet of the CO Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116026 Share on other sites More sharing options...
[Mi...] Posted August 17, 2018 Author Share Posted August 17, 2018 SO they are telling me that as long as the width is not over 1.05 they are good. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116028 Share on other sites More sharing options...
[Ri...] Posted August 17, 2018 Share Posted August 17, 2018 Does this feature fit into something? Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116030 Share on other sites More sharing options...
[Mi...] Posted August 17, 2018 Author Share Posted August 17, 2018 Yeah its a snap ring. Fits inside another part into a hidden groove. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116032 Share on other sites More sharing options...
[Jo...] Posted August 17, 2018 Share Posted August 17, 2018 Okay so this is probably an ISO print. That changes things. The principle of independency is default in ISO so size does not control form unless it is actually invoked using the circle E symbol. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116034 Share on other sites More sharing options...
[Mi...] Posted August 17, 2018 Author Share Posted August 17, 2018 Yeah its ISO and no there is no E req on this part. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116036 Share on other sites More sharing options...
[Ri...] Posted August 17, 2018 Share Posted August 17, 2018 Okay, so if there is a potential of approving parts that will not fit in the hidden groove, then a prudent approach for the evaluation is warranted. 40 micron tolerance for size is snug. Saying that the print allows these parts to exceed that tolerance by 5 times that is a little nuts. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116038 Share on other sites More sharing options...
[To...] Posted August 17, 2018 Share Posted August 17, 2018 My guess is the .8 wire diameter is not going to be the issue. They just want the ring to be flat. Or, am I missing something? Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116040 Share on other sites More sharing options...
[Ri...] Posted August 17, 2018 Share Posted August 17, 2018 Tom "Fleckhead" Oakes, I would agree with except for the +/- 0.02 tolerance. That implies to me, that it's critical. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116042 Share on other sites More sharing options...
[To...] Posted August 18, 2018 Share Posted August 18, 2018 Well there certainly seems to be a lot of assumptions flying around as we really don't know the entire story. I was making the assumption they may have purchased wire with a specified tolerance and were only forming the rings. If they are manufacturing the wire, then I agree the tolerance may be important. Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116044 Share on other sites More sharing options...
[Aa...] Posted August 20, 2018 Share Posted August 20, 2018 Please sign in to view this quote. Yeah...I definitely jumped on the assume-it's-Y14.5 bandwagon. I would guess that's what your engineers did, too, but that's just speculation. 😉 While all the Y14.5 talk wasn't really applicable to the OP, it did throw some light on part of that standard that doesn't usually see the light of day. BTW, Mike, don't forget to toggle the switch in Calypso so that it evaluates according to ISO instead of ASME. 🤣 Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116046 Share on other sites More sharing options...
[Mi...] Posted August 20, 2018 Author Share Posted August 20, 2018 This part is actually bent into a "C" shape from our supplier. This in turn is inserted/pressed into a ID. The ID has a groove cut into it about 2 mm down. This part springs back if you will into that groove. So its a "spring washer" as we call it. They are still sorting with a 1.05 tolerance on the part which does not make sense to me! Link to comment https://qualityforum.zeiss.com/topic/20462-flatness/#findComment-116048 Share on other sites More sharing options...
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