SteveM wrote: ↑Sat Jan 20, 2018 10:00 am
I suspect if I tested my "beater" mic (yes, I have "beater" mics), I would find they were off.
My "beater" mics are the ones I take with me to flea markets so that I can identify stuff, like morse vs B&S tapers.
Oh, yeah!
I, too, have a "beater mic", an 0-1". It's the tenth reading mic I purchased those many years ago when I got started in the trade (purchased early in 1958). The same mic I used to trust to .000050", reliably, when I worked in precision grinding.
Several years ago I took a close look at the anvil and spindle faces (carbide) and was shocked to see them worn dull. I couldn't live with that condition, although I also had no interest in abandoning the micrometer, so I ordered a new one, exactly like the worn one, in spite of owning, in addition, a Starrett T221XL Hi-Precision Micrometer.
The new mic sits, unused, in my tool box, but I now feel covered for that day when I need a trusted micrometer.
Bottom line---micrometers do wear out. Even when cared for properly.
H