How to use a caliper
type inside micrometer

Shop for Micrometers

Step 1 – Adjust micrometer

Turn the ratchet speeder until the micrometer reads the lowest value of its range. Because of the design of the jaws, caliper micrometers typically start with a range of 5 to 30mm.

Step 2 – Insert micrometer into hole

Carefully insert the measuring faces into the hole or aperture you are measuring.

Step 3 – Rotate thimble

Rotate the thimble using the ratchet speeder until the measuring faces of the micrometer are near the surfaces to be measured.

Carefully continue rotating the ratchet until contact is made and the spindle no longer rotates. The ratchet will keep turning, applying the correct amount of force for an accurate measurement.

Step 4 – Lock spindle

Turn the lock nut or lever to secure the distance between the measuring faces then remove the micrometer if required.

Step 5 – Read measured value

Read the measured value (see How to read a micrometer).