Common Methods of Measuring the Diameter of a Hole

[TomG]

Funny you should mention that Ed, reading the micrometer was next on my list. When I taught machine shop, I used to teach how to read the micrometer by associating the divisions on the thimble and barrel to pocket change. The ones on the thimble were pennies (1-25), each of the four marks between the numbered divisions on the barrel were quarters (4) and the numbered lines on the barrel were dollars. All you need to do is add 'em all up to get the measurement.

I'll need to check out the close-up capability of my camera, but I may be able to do that one right now.

Tom