"Jim Stewart" wrote in message
.. .


I noticed that in order to get them to wring
together, the surfaces had to be close to
perfectly clean. I assume they have to be
re-oiled after use.

To wring together properly, they do have to be clean and dry. Cheaper sets
sometimes benefit from a tiny bit of the grease made for that purpose, good
ones shouldn't need it.

Does anyone know what the accepted procedure
is for testing mikes and calipers? Some
sort of progression of blocks that serves
as a worst-case test?

Pick the intervals that you want to check them at, but avoid anything that
would come to an even interval for a caliper, use odd and random intervals.
For micrometers, maybe zero, 1/4, 1/2 /34, etc but always include at least
one that will come out a half turn of the thimble from the zero to check for
drunken threads, it does happen.

Rich