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Micrometer

Reading a micrometer is considered a basic skill for any machinist and should be considered so for any fabricator. In the following pictures I will explain how to read a regular .001 graduated micrometer (mic). This will be same process for any .001 graduated mic, whether it is a depth mic or C-mic. The first thing you will notice is the two barrels. The internal barrel with numbers on the shaft in the horizontal. The external barrel with the numbers on the shaft in the vertical. The external barrel is the only component that moves in this case. If you look closely at the internal barrel you will see the various tic marks. The tic marks above the horizontal line represent .050. The tic marks below each represent a multiple of .025. You will also see the numbers on the external barrel they represent .001 of an inch. So the number 1 actually means .001 of an inch and 2 represents .002 and so on.

In this photo above the mic reads .301. The reason for this is the number 1 on the external barrel lines up with internal barrel as demonstrated.

In this photo above the mic reads .325. As it is sitting on the first tic mark after .300.

In this photo above the mic reads .350 As it is sitting on the second .025 tic mark and first .050 tic mark after .300

In this photo above the mic reads .375. As it is sitting on the third .025 tic mark after .300

In this photo above the mic reads .398. This is found by adding .023 to .075.

In this photo above the mic reads .399. This is found by adding .024 to .075

Finally we come too the last photo in which the mic reads .400. Mics that are graduated in the .001 are fairly easy to read for a beginner and should pose no issue. Fecke – KJ4ZRZ

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