When To Not Use GD&T
Sometimes people attempt to use GD&T for things that it was not meant to handle. Below are some examples of situations in which GD&T should not be used
Non Part Features - GD&T is meant to be used on part features. It should not be used on things that are not part features. For instance, sometimes it is desirable for assembly reasons to mark a part by scribing a line or by using a paint dot. Such things are not part features. They cannot be located or oriented with GD&T
Another subject that is not part of GD&T is surface finish. Surface finish is an important subject in itself but just not part of GD&T.