USING A CENTER GAGE
The center gage is used to set thread cutting tools. Four
scales on the gage are used for determining the number
of threads per inch. The gage is also used to check cut
threads and the scales are used to measure threads per
USING A SCREW PITCH GAGE
If the pitch of a thread is not known, it can be
determined by comparing it with the standards on the
various screw pitch gages.
Place a blade of a gage (1) over the threads (2),
and check to see whether it meshes; if not,
successively check each blade of the gage
against the thread until it meshes.
The pitch can be read off the correct blade. The
blades are made pointed so that they can be
inserted in small nuts to check inside threads as
well as outside threads.
USING A SMALL HOLE GAGE
The small hole gages perform the same function as
telescoping gages, except that they are used in smaller
Fit the ball-shaped point (1) into the hole or slot
Expand the ball-shaped end by turning the
screw (3) at the end of the handle.
Use micrometer to gage the measurement.