Drawing standard - dimensions include paint or not
Drawing standard - dimensions include paint or not
(OP)
I have a query - do engineering drawings include the paint thickness within the dimensions and tolerancing of a drawing?
IE if a drawing specified a dimension as 20mm +/- 0.002 but also called for a paint process should you make the part small to build in an allowance for the paint?
IE if a drawing specified a dimension as 20mm +/- 0.002 but also called for a paint process should you make the part small to build in an allowance for the paint?
RE: Drawing standard - dimensions include paint or not
So to American standards the drawing has to explicitly state whether the dimension applies before or after painting. If the drawing doesn't say then it's ambiguous and arguably parts can't be rejected either way.
I'm not sure with ISO does though.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Drawing standard - dimensions include paint or not
If paint thickness was a critical value I would always add the information on the drawing. I learned that it is better to give information when important, regardless what the standard says. Who's benefit is it, if parts do not fit but the drawing complies to the standard?
RE: Drawing standard - dimensions include paint or not
Next question: " Why would anybody specify +/- 0.002 on a painted surface"? Smells like the drawing was made by someone not having the slightest idea of 0.002 mm.
RE: Drawing standard - dimensions include paint or not
RE: Drawing standard - dimensions include paint or not
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?