Parallelism question

[lessfull]

Hi everyone
I have a tolerance that states "// 0.025/ 100 in to datum A" in milimeters

I'm interpreting that means parallelism within 0.025 mm over a 100 mm diameter area relative to datum A.
Is it correct?

Tanks

 

[Belanger]

Almost correct, except that I'm not sure about the "diameter" thing. To say that, there would be a diameter symbol Ø before the 100; without it we would just assume linear length of 100 (although that too can be confusing because I would usually show another dimension, such as 100 X 12).
I also wonder what the "in" means after the 100 -- did you mean mm? It would be strange to mix a millimeter tolerance with an inch dimension on the local segment.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

 

[lessfull]

Well, i was trying to put in words what appears in the drawing, the "in", i meant it to relate the values to the datum A, the "in" doesn't appear in the drawing. Is only milimeters the tolerance.

Trying another time:

" //0.025/ 100 "

it's what appears before the reference to datum A. The diameter was an interpretation i made but my initial tought about it was a linear section of 100 mm, but then only appears as i wrote above without anything after the "100".

Tanks for you attention