"Randy Replogle" wrote in message
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FWIW, I was taught to apply "nose oil" to gage blocks before wringing.
Just rub a finger down your nose and smear a film on the blocks.
I was also told once that when clean blocks are wrung together the two
blocks actually share electrons which causes them to stick so well.
Not sure about that.
Randy Replogle
--
Randy Replogle

Blocks should be wrung perfectly dry. If they won't, there's a problem with
one of them, maybe both. Anything applied to blocks will change the
overall size, albeit only a few millionths. That defeats the purpose of
gage blocks, particularly if a stack is developed with several small blocks.

The idea of a miniscule film changing size appreciably was driven home for
me when the QC department had requested a dial indicator that was mounted on
a steel pin, which, in turn, would be inserted in a bore and spun as a
concentricity check against another surface. It goes without saying that
the fit, in order to work properly, had to be barely a slip, nothing more.
Diameter was about 1" (this was back in the early 60's, so my memory has
faded) and maybe 3" long. The only way to judge size for this particular
job was to fit the bore to the existing pin. I was shocked when I was
attempting to mate the parts while they were still wet from honing and they
wouldn't go, although they seemed to want to. With the parts washed in
solvent and air dried, they fit perfectly, but so much as finger prints
prevented the fit. Very sobering.

Harold