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Examine the grinder plate for cracks before
each sharpening. If tramp metal has been
ground, examine the plate very carefully.
A plate that is free of cracks will have a
distinctive ring if struck with a small metal
rod. Strike the edge of the plate on the 30°
chamfer. Do not use a mall to ring the plate,
a gentle tap is sufficient. Plates that are
cracked will not ring well, and often you will
simply hear a thud.
Notice the tramp metal stuck in one of the
holes. The tramp metal must be removed.
Note the gouges that extend from hole to
hole. These gouges must be ground out.
The sharpened grinder plate should have
fine lines extending from the outer edge,
through the center of the plate, then back to
the outer edge. In drafting terms the symbol
would be
22
30° CHAMFER
Rather, place the plate over the center of the
surface grinder table, like this!
CRACK
TRAMP METAL
WEDGED IN HOLE
GOUGES
EXTENDING
BETWEEN
HOLES
R
BAD
GOOD
When grinding plates,
do not
place the plate
at the outer edge of the surface grinder table.