I mean... That's a completely different kind of tool I don't know why you think that's applicable.
These kinds of standards can corrode and change or need to be re-lapped, or just wear. That doesn't ruin them, but you need to know how long they actually are so you can zero the micrometer correctly.
THE_CENTURION t1_j92q9rn wrote
Reply to comment by Occhrome in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight
I mean... That's a completely different kind of tool I don't know why you think that's applicable.
These kinds of standards can corrode and change or need to be re-lapped, or just wear. That doesn't ruin them, but you need to know how long they actually are so you can zero the micrometer correctly.