I can top that one. This was done by one of the inspectors I work with:
A 2" diameter bar is going to be welded to the of these 2 tubes to create an "A" shaped support. We needed to verify there was enough stock to cut radii into them for the 2" bar to fit. This guy literally cut a 2" diameter piece of card stock, taped it to the end or the CMM probe, and positioned it to where the 2" bar would be located. This picture was one of 3 from his official report verifying the extra stock was present.
