- 1). Clean the entire micrometer to remove any excess dirt or oil.
- 2). Measure both standards with the micrometer to ensure that the standards have the same measurement and that the micrometer is off by the same amount on both. If one measures larger, you may need to replace your standard.
- 3). Tighten the micrometer jaws around a correct standard and lock into place using the lock nut.
- 4). Locate and loosen the ratchet stop at the end of the micrometer. In newer models, the ratchet stop is a black metal knob that protrudes from the end opposite the jaws and is used to lock the barrel in place. If your model does not have a ratchet stop, remove the screw at the end of the micrometer to free the knurled nut. Loosen the nut to allow the barrel to move freely.
- 5). Turn the barrel until the micrometer shows the correct measurement for the standard.
- 6). Tighten the ratchet stop or tighten the knurled nut and reinsert the cap screw. Unlock the jaws and remove the standard.
- 7). Test the micrometer on the standard. If the measurement is still off, repeat the process.
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