Depth Micrometer

Depth Micrometer

Depth Micrometer

Depth micrometers are excellent for determining the depth of small holes, extruded cuts, or odd geometries unable to be measured by inside micrometers or outside micrometers. These micrometers only come in the 1" variety in the Gauss Johnson shop. Here is a picture of the anatomy of a depth micrometer:

How to Operate: 

Depth micrometers have a base that is placed flat against a surface and the thimble is twisted to extend the rod. The rod contacts the bottom of the hole or slot and tends to lift the base. When this occurs the user is to retract the rod until the base is returned to its flat position and the user will twist the cap until it clicks. Common practice is to move or slide the depth micrometer along the flat surface to ensure there is drag along the bottom of the hole or slot. Once this occurs the user will engage the lock nut and remove the depth micrometer for measurement reading.

How to Read: 

Depth micrometers are read in the same fashion as the outside micrometer. However, the numbers are placed in the opposite order as those displayed on an outside micrometer. For example the following depth micrometer reads .3765": The numbers read the same, but are placed in opposing order. This can be disorienting to those familiar with outside micrometers. Don't over-think the measurement, it is read the same as an outside micrometer.