Hole location dimension when TOP is used
Hole location dimension when TOP is used
(OP)
I have attached drawing having following interpretations when GD&T TOP position tolerance used.
Pic 1: All Holes are dimension from DRF
Pic 2: Holes are (Y axis) dimensioned from hole to hole. (Middle and upper hole Y axis dimensions are not from DRF)
Explain how each interpretation works. Inspection would consider both interpretations are same?
Pic 1: All Holes are dimension from DRF
Pic 2: Holes are (Y axis) dimensioned from hole to hole. (Middle and upper hole Y axis dimensions are not from DRF)
Explain how each interpretation works. Inspection would consider both interpretations are same?





RE: Hole location dimension when TOP is used
RE: Hole location dimension when TOP is used
RE: Hole location dimension when TOP is used
RE: Hole location dimension when TOP is used
RE: Hole location dimension when TOP is used
Thus they are not subject to tolerance accumulation.
Think of a drawing with basic dimensions and FCFs as description of a gauge you have to build to check the part.
No matter how you dimension it, the pins will be located in exactly the same places.
I hope it helps.
"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future
RE: Hole location dimension when TOP is used
Certified Sr. GD&T Professional
RE: Hole location dimension when TOP is used
John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
RE: Hole location dimension when TOP is used
One minor point w/r/to the drawing views. Drafting protocol uses arrowheads only when the arrow point is touching an object line or a boundary line. If you want to call out a datum on a surface you should use the "dot" terminus or "integral" terminus, for example, when the terminus is not touching an object line or boundary line. Just my 2¢.
H. Bruce Jackson
ElectroMechanical Product Development
UMD 1984
UCF 1993