PRECISION MEASURING AND GAGING - OD1642 - LESSON 1/TASK 2
bend or kink.
A good way to get the "feel" of using a thickness gage
correctly is to practice with the gage on openings of known measurements.
(6) Radius Gage.
(a) The radius gage (figure 22) is used to check, in any position
and at any angle, both inside and outside radii.
This gage is often
underrated in its usefulness to the machinist. The blades of the fillet and
radius gages are made of hard-rolled steel. The double-ended blades of the
gage have a lock which holds the blade in position. The inside and outside
radii are on one blade on the gage.
Each blade of the gage is marked in
64ths. Each gage has 16 blades.
FIGURE 22.
FILLET AND RADIUS GAGES.
(b) Whenever possible, the design of most parts includes a radius
located at the shoulder formed when a change is made in the diameter. This
radius gives the part an added margin of strength at that particular place.
When a square shoulder is machined in a place where a radius should have
been, the possibility that the part will fail by bending or cracking is
increased. The blades of most radius gages have both concave (inside curve)
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