Lesson 4/Learning Event
Thickness (feeler) gages are used in one of two ways, as a means for
determining a measure or as a means for adjusting to a definite limit.
Figure 55, Part A, shows a thickness gage being used to check piston ring
gap clearance in a cylinder bore. A long blade thickness gage is being used
to determine the fit between large mating surfaces in Figure 55, Part B. By
combining blades, it is possible to measure a wide variation of thicknesses.
USING THICKNESS (FEELER) GAGES
Wire and Drill
The use of a drill gage is illustrated in Figure 56, Part A. The size of a
drill is being determined. The drill size or number and decimal size are
stamped on the gage beside each hole.
A chart on the gage indicates the
correct size of drill to use for a given tap size. To determine the size of
both sheet stock and wire, you can use the wire gage shown in Figure 56,
USING DRILL AND WIRE GAGES (PARTS A AND B)