Hello to you all, I am new to this forum.
I try to find experts for the ISO drawing standard, I hope I am in the right place.
Here are a few questions :
1. First I would like to know, if I put a dimension, let say a diameter of a cylinder with a tol. of 0/-0.2. does it means that the straightness of cylinder must be 0.2 or lower? or must I state the Geometrical relation along side with the tolerance, what does not make real sense.And In which Std. does this roles stated?
2. If I understand the Iso 8015 correctly, It means, if stated in the drawing title block, that the dimension's tol. do not apply for the geometric relation (as in the previous question) , hence the "Principle of independency" apply. If so, I could write diameter tol. of 0/-0.2 and straightness of 1. If what I wrote is correct than how do I measure the dimension of the cylinder?
ISO states that by default the principle of independency applies to features of size unless:
1) The Envelope Requirement is specified (circle E).
2) A Geometrical tolerance is specified with/to the feature of size that would designate a boundary on that feature of size, like a MMR.
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