i have one and they work fine. the principle is pretty simple and, therefore, reliable: one end of the calipers measures the exterior diameter of a lid (or any round piece) and the other end measure -- to the same length -- the interior. so, you throw a lid and set the calipers, then throw the pot and use the other end to guage the diameter, or vice versa. i don't think they are a "wonder tool" since you can do the same thing with a stick in the studio, but they can be handy at times.
- posted
20 years ago