Runout on a flat surface in a stack
Runout on a flat surface in a stack
(OP)
We have many instances where runout was used on a flat surface. The basic premise is the engineer at the time was attempting to control the "wobble" on that surface (basically perpendicularity)and back in the day TIR was the goto for prints. If given the choice I would write a request to change all of these and replace with either perpendicularity or profile (but alas...). My question is, when performing a stack-up on a part where the end face has surface runout applied what effect does it have? Should it be added as a ± in the calculations or does Rule #1 come into play and the runout only refines the zone?





RE: Runout on a flat surface in a stack
I think can be eitherway.
What has been concluded in this thread:
http://www.eng-tips.com/viewthread.cfm?qid=430633
is that the runout is not controlling the surface location!
RE: Runout on a flat surface in a stack
So, no size control, more of a refinement.
"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future
RE: Runout on a flat surface in a stack
Thanks for the input!
RE: Runout on a flat surface in a stack
I mention this because if you're thinking of circular runout, then it's not the same as perpendicularity. Only if the print uses the total runout symbol can we say that it's equivalent to perpendicularity.
RE: Runout on a flat surface in a stack
RE: Runout on a flat surface in a stack
But if you're looking at a stack for clearance near that end face (so it doesn't rub against another piece), then total runout (perpendicularity) would be a factor. Circular runout wouldn't -- it would allow for a pointed/crowned face, so I think you'd have to look for another tolerance that controls the orientation and form of that face.