Porter Cable PCB575BG Manuel D'instructions page 14

GENERAL OPERATION
CAUTION
!
Keep all bystanders a safe distance away from
the tool and not in direct line, front or back of the
grinder.
1. Your bench grinder has a medium wheel (60 grit)
for medium material removal and general purpose
grinding, and a coarse wheel (36 grit) for fast material
removal.
2. To operate the bench grinder, always wear safety
glasses and turn the tool on while standing at the side
and not in front of the grinder. Allow it to reach full
speed before grinding.
3. Hold the work piece firmly against the tool rest. Hold
very small pieces with pliers or other suitable clamps.
4. Feed the work piece smoothly and evenly into the
grinding wheel.
5. Move the work piece slowly and avoid jamming the
work piece against the wheel. If the wheel tends
to slow down from excessive force, you should
occasionally release the pressure to let the wheel
return to full speed.
6. Grind only on the face of the grinding wheel and
never the side of it. (Some wheels are designed
for side grinding and will say so on their blotters/
cardboard disc.)
CAUTION
!
Prolonged grinding will cause most materials
to become hot. Use care when handling such
materials.
SCISSORS
If possible, take the scissors apart to make the
sharpening operation easier and safer. Remove material
only from the outside surface and work from the heavy
end of the blade toward the tip.
KNIVES
Remove metal from both faces of most knives, working
from the heavy end of the blade toward the tip.
SCREWDRIVERS
The end of a properly sharpened screwdriver will be
a perfect rectangle, absolutely flat and perpendicular
to the center line of the shank. The two sides and two
faces will taper outward from the edge of the shoulder
or shank. They should be flat with intersecting faces
perpendicular. Hold each face of the screwdriver against
the wheel to true it up, then ease the end straight into
the stone to grind it true.
TWIST DRILL BITS (FIG. Q)
Drill bits are best sharpened on a sharpening jig,
available at most hardware stores, but can be "dressed
up" on your grinder. Begin on one side of the point at
the existing angle, then twist the bit while maintaining a
constant angle with grinding surface. Sharpen only the
tip. This technique requires considerable practice, so
take your time and make a few "dry runs" first with the
grinder off. Be sure to maintain the original cutting edge
angle as this is important to the efficiency of your bits.
One tool rest has a V-groove that is correctly angled for
most drill bits.
Fig. Q
LAWN MOWER BLADES
Lawn mower blades are usually sharpened on only
one side and dressed up slightly on the other. After
sharpening, be sure to balance the blade by removing
additional material from the heavy end. There are a
number of inexpensive cone balancers on the market
for this purpose. Unbalanced blades can cause serious
crank shaft damage to your lawn mower. Always remove
spark plug wires from the mower before servicing the
blades to prevent accidental starting.
DRESSING A GRINDING WHEEL (FIG. R)
A wheel dressing tool is provided with the grinder. Bring
the dressing tool forward on the tool rest until it touches
the high point on the face of the wheel. Dress the wheel
by moving the dressing tool back and forth. Repeat this
operation until the face of the grinding wheel is clean
and the corner of the wheel is square. NOTE: DO NOT
use the wheel dressing tool on wire wheels.
Fig. R
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