Difficulty Level

Tools/Supplies Needed:

• imperial vernier or standard micrometer

Procedure:

• make sure the lock is off so the thimble moves freely
• ensure that the micrometer is correctly zeroed and both measuring faces are clean
• also make sure the part you are measuring is clean too
• open the spindle to ensure it will fit over the item you are measuring, then close the sleeve and anvil against the item using the ratchet
• the ratchet ensured you apply an equal amount of pressure which ensures accuracy
• set the lock to ensure the micrometer does not move
• depending on the size of micrometer you are using (0"-1, 1"-2", 2"-3", etc), this will determine what inch mark you are at X.000"
• move along to the first decimal place, which in written on the sleeve and will be determined which is closest to the edge of the thimble 0.X00"
• now using the lines between the 0.X00" markings, they each equal 0.025", determine which is still viewable and closest to the thimble
• now using the scale on the thimble, determine which line is just before the horizontal vertical line on the sleeve, take that number and add it to the 0.0XX quarter number taken from the sleeve from the previous step
• now you will have your final measurement
• if you are using a vernier scale or what an accuracy to ten thousandth of an inch, look at the vernier towards the backside of the micrometer on the sleeve
• determine which line on the vernier scale on the sleeve alines best with the lines on the thimble which gives you the final number 0.000X"