TM 9-243
TYPES AND USES - Continued
THREAD CUTTING TOOL GAGES
Thread cutting tool gages are hardened steel plates with
cutouts around the perimeter. Each cutout is marked
with a number that represents the number of threads per
inch.
These gages provide a standard for thread cutting tools.
They have an enclosed angle of 29 degrees and include
a 29 degree setting tool. One gage furnishes the correct
form for square threads and the other for Acme standard
threads.
FILLET AND RADIUS GAGES
The blades of fillet and radius gages are made of hard-
rolled steel. The double-ended blades of the gage have
a lock which holds the blades in position. The inside and
outside radii are on one blade on gage (A). The other
gage (B) has separate blades for inside and outside
measurements. Each blade of each gage is marked in
64ths. Each gage has 16 blades.
DRILL POINT GAGE
The drill point gage consists of a 6-inch hook rule with a
59 degree sliding head that slides up and down the rule.
The sliding head can be locked at any position on the
rule and is graduated in 1/32 inch. This gage is used to
check the accuracy of drill cutting edges after grinding. It
is also equipped with a 6-inch hook rule. This tool can be
used as a drill point gage, hook rule, plain rule, and a
slide caliper for taking outside measurements.
WIRE GAGES
A wire gage is circular in shape with cutouts in the
outside edge. Each cutout gages a different size wire,
from 0 to 36 of the English Standard Wire Gage. A
separate gage is used for American standard wire and
another for U.S. Standard sheet and plate iron, and
steel.
Similar gages are also used to check the size of hot and
cold rolled steel, sheet and plate iron, and music wire.
16-4
