 Welcome to this module on Micrometer Adjustment. Adjustments to micrometers are rarely needed, but in some cases adjustments may be necessary. Before any adjustments are made to any measuring instruments, you must first make sure that the instrument is clean and in good condition. Also, in some manufacturing environments, adjustments to measuring instruments can only be done by the inspection department. Clean the micrometer by lightly closing a piece of paper between the anvil and spindle surfaces of the micrometer. Slide the paper out from between the surfaces and blow out any paper residue that clings to the spindle or anvil. Bring the spindle and anvil together using the ratchet or the friction thimble. Use the same gauging force when checking the micrometer as you would use when measuring a part. Check the zero point on the barrel against the index line located on the sleeve. If the zero point in the index line are not in alignment, an adjustment is necessary. If an adjustment is necessary, use the spanner wrench, which was included with the micrometer, to turn the sleeve until the line on the sleeve coincides with the zero line on the thimble. Adjustments to the micrometer are made with the spindle and sleeve in contact with one another. If any play has developed and the spindle screw threads due to wear on the spindle, adjustments to the spindle nut may be necessary. To adjust the spindle nut, back off the thimble until the spindle nut is visible. Insert the spanner wrench in the slot of the adjusting nut and tighten just enough to take out the play. You have completed this learning activity, micrometer adjustment.