inspection significant figures
inspection significant figures
(OP)
When a dwg specfies the locational tolerance of part soldered to a board as example +/-.005, is a part that measures .0051 off location out of tolerance? Do typical quality/inspection guidelines mandate that non specified significant figures are zeros as opposed to +/-.0054999.
I find it hard to believe that common sense, especiallly for run of the mill, non safety critical parts that rounding off/rounding down isn't practiced.
I find it hard to believe that common sense, especiallly for run of the mill, non safety critical parts that rounding off/rounding down isn't practiced.





RE: inspection significant figures
RE: inspection significant figures
For something like that, the only technical out is if your measurement accuracy can cause a conforming part to exceed the spec.
TTFN
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RE: inspection significant figures
-handleman, CSWP (The new, easy test)
RE: inspection significant figures
Splitting hairs...but I have 3 parts hung up bc of this hair splitting....
RE: inspection significant figures
RE: inspection significant figures
RE: inspection significant figures
So +.0051 is out of specification.
If the part doesn't need to be accurate to +-.0050000000 then the drawing should be changed to show a larger tolerance. The tolerance should be chosen by function while meeting manufacturing capabilities.
As to the inspection specific aspect of this, I'd look in forum286: QC, Inspection & Testing engineering as I think similar has been asked before.
A problem with rounding is there are different techniques, you'd have to formally standardize a technique.
KENAT,
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RE: inspection significant figures
TTFN
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RE: inspection significant figures
Ted
RE: inspection significant figures
"All limits are absolute. Dimensional limits regardless of the number of decimal places, are used as if they were continued with zeros. To determine conformance within limits, the measured value is compared directly with the specified value and any deviation outside the specified limiting value signifies nonconformance with the limits."
RE: inspection significant figures
Once you've done that, you're done with niggling with test results; they are either in spec or not, no exceptions.
Likewise, you are probably violating your ISO-9000 certification with this line of investigation, since your procedures should have already been formalized and approved for production.
TTFN
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RE: inspection significant figures