We found it!!…. It’s a new drawing..
It’s a GS90013:2002-07 spec. from Germany.
It means “For connecting faces and function fasces as per GS 91006-1 Supplement 1”
A normal profile of a surface pertains to the part in the part print only. This is calling a profile of a mating surface of a different part on a different print. I know it’s weird, I’ve never seen anything like that either.
Folks, this is from the same nation that brought you ISO 2768 and some of the quirks there in and quirky interpretation there of. Are we really surprised?
In my view, things like this come out of the European guidelines because they are still focused on precision rather than accuracy.
Precision is the ability for one factory to make parts that fit together (make it so that it fits other parts we build).
Accuracy is the ability for any factory to make parts that fit together (tolerances are absolute limits and consistant regardless of location or processes, so parts made anywhere can be used universal for the same design).
It is a bit ironic that this is the direction the engineering ISO and DIN standards have taken since the rest of ISO relies on the ideal of "say what you do, do what you say". When the engineering related ISO guidelines are employed, it's more of "say what you hope for, hope to get what you want"
(When their companies go through a million lawsuits about confused meanings of the standards, I'm guessing they will slowly move closer to the American POV (i.e., Rule #1 and the removal of clauses about things being ok if they happen to fit).)
