Our other sites:

How to zero a micrometer?

How to zero a micrometer

Shop for Micrometers

Zeroing your micrometer

It is important to check that your micrometer is properly calibrated to ensure that the measurements you take are accurate and reliable.   Before using your micrometer, It is important to check that it is properly zeroed to ensure that your measurements are accurate and reliable.

This means that when both the anvil and spindle measuring surfaces of the micrometer are closed together, the scales will read zero.

The sleeve of the micrometer is adjustable, allowing you to line up the index line with the zero (0) on the thimble.

Before checking the zero position, ensure that the measuring surfaces are clean and free from defect.

Zeroing the micrometer uitilises the same proceedure as when measuring.

To do this, turn the ratchet towards you to close the spindle until it makes contact with the anvil.    Then check that the 0 on the thimble lines up with the index line on the sleeve. To check the zero position, rotate the thimble using the micrometer ratchet speeder until the spindle is close to the anvil.

Carefully turn the ratchet as you approach the anvil and continue turning until the spindle stops rotating. The ratchet will continue to turn, applying the correct amount of force for an accurate measurement of the zero position.

Using the micrometer thimble alone requires a degree of skill and practice to achieve the correct “feel”.

Then check that the zero (0) on the thimble lines up with the index line on the sleeve.

If this is not the case, your micrometer will need to be recalibrated using the adjusting spanner wrench provided with the tool. Check several times, by repeatedly backing off the spindle and then re-checking the zero. If the Zero lines up repeatedly, then your micrometer is ready for use.
If the zero fails to line up with the index line, the micrometer will need to be re-zeroed using the adjusting spanner usually provided with the instrument.With the two measuring faces in their correctly zeroed position, use the locking device to lock the spindle so that nothing moves.
Wonkee Donkee says: 'As the calibration of micrometers designed to take  measurements greater than one inch cannot be checked  by closing the gap between the measuring faces, they  are supplied with metal standards. These are used as a  gauge for micrometers to measure dimensions  between 2 and 3 inches, for example.'
Although the sleeve of the micrometer is fixed tightly to the frame, it is not permanently attached.     Use the spanner wrench to turn the sleeve until the 0 aligns with the index line. Locate the hook of the supplied spanner into the hole at the base of the sleeve. Carefully turn the sleeve until the index line aligns with the zero.

Unlock the spindle then repeat the zeroing procedure until the zero repeatedly lines up with the index line.

Wonkee Donkee Tools