TM 9-243
TYPES AND USES
Grinders are mechanical devices which allow you to
reshape, form, and sharpen metal cutting tools or other
tools. A grinder consists of an abrasive wheel mounted
on a rotatable shaft. The abrasive wheels are available
in varying degrees of coarseness, depending upon type
of metal to be ground. Sharpening stones may be either
natural or artificial. Natural stones are of a finer grain
than the artificial stones.
BENCH GRINDER
Bench grinders are used for reshaping and sharpening
chisels, drills, hatchets, and other similar small hand
tools.
The bench grinder consists of a clamp (1), a rest (2), an
abrasive wheel (3), a handcrank (4), and an encased
gearing assembly (5). The clamp is used for fastening
the grinder to a working surface. The rest supports tools
which are being ground. It is adjustable and may be
moved from side to side. The abrasive wheel may be
changed depending upon the type of metal being
ground.
VALVE GRINDER
The valve grinder is a hand-operated special grinder. It
is used for grinding the valve seating surfaces on com-
bustion engines. It grinds with cutting blades on a rotat-
ing shaft instead of an abrasive wheel. It consists of an
encased gear housing (1), a handcrank (2), inter-
changeable shafts (3), cutting blades (4), and a suction
cup (5). The suction cup is used in place of a blade to
grind non-slotted valves to fit seating surfaces.
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