Combining Position and Perpendicular
Combining Position and Perpendicular
(OP)
I have a design with a pattern of 12 pilot holes in a rectangular block. Usual datums of A being the flat bottom, B one edge and C the other edge at 90 deg. I can be generous on the placement of each hole both wrt to ABC and dimension between holes. But I do need each hole perpendicular .001 dia to A.
We use the 1994 version of Y14.5 and looking thru it all the true position composite blocks say that that the second line (related to datum A only) controls hole to hole tolerance in addition to perpendicularity to A. I do not want to force .001 tolerance hole to hole so is there a way to call this out legally?
My thought is to use a single line position block then add a a perpendiclar frame below it that would look like this:
12X dia .125 +.003 -.000
pos/dia .020/A/B/C/
perpendicular/ dia .001/A
Intent of above seems clear but I can find no examples in 14.5 that show this. Is it legit?
We use the 1994 version of Y14.5 and looking thru it all the true position composite blocks say that that the second line (related to datum A only) controls hole to hole tolerance in addition to perpendicularity to A. I do not want to force .001 tolerance hole to hole so is there a way to call this out legally?
My thought is to use a single line position block then add a a perpendiclar frame below it that would look like this:
12X dia .125 +.003 -.000
pos/dia .020/A/B/C/
perpendicular/ dia .001/A
Intent of above seems clear but I can find no examples in 14.5 that show this. Is it legit?





RE: Combining Position and Perpendicular
RE: Combining Position and Perpendicular
Unfortunately you mentioned Y14.5-1994; 2009 version of the standard shows your case on Fig. 6-14 and 6-15
RE: Combining Position and Perpendicular
Yes, your approach is a way to go (if you still need another confirmation).
RE: Combining Position and Perpendicular
So my understanding is that Y14.5-1994 does allow this approach even tho they show no such examples.
RE: Combining Position and Perpendicular
Always keep in mind paragraph 1.1.4. As much as we all like pretty pictures it's the text that really matters.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Combining Position and Perpendicular
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RE: Combining Position and Perpendicular
John-Paul Belanger
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Geometric Learning Systems
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