using profile of a surface tolerance on size controls the form better
 

using profile of a surface tolerance on size controls the form better
November 2005 Tip-of-the-Month
Using Profile of a Surface Tolerance on Size controls the form better.
Some folks wondered why profile of a surface was used to control the size of the spherical diameter rather than just a size tolerance. The answer is that the form is controlled better.
This chart illustrates that as the size of the feature approaches either the largest or smallest size, the form of the feature must be held better.
If a size dimension and tolerance had been applied to the spherical feature, the form error could increase if the feature was made closer to the LMC size.

回复: using profile of a surface tolerance on size controls the form better
 

good

回复: using profile of a surface tolerance on size controls the form better
 

i like it