2610067378 05-21 GSB18V-535C.qxp_GSB18V-535C 5/19/21 1:37 PM Page 20
maximum safe operating speed is not
exceeded by the nameplate speed of the tool.
Do not exceed the recommended drill bit
diameter.
Drilling Wood
Be certain workpiece is clamped or anchored
firm ly. Always apply pressure in a straight line
with the drill bit. Maintain enough pressure to
keep the drill "biting".
When drilling holes in wood, twist bits can be
used. Twist bits may overheat unless pulled out
frequently to clear chips from flutes.
Use a "back-up" block of wood for work that is
likely to splinter, such as thin materials.
You will drill a cleaner hole if you ease up on the
pressure just before the bit breaks through the
wood. Then complete the hole from the back
side.
Drilling Metal
There are two rules for drilling hard materials.
First, the harder the material, the greater the
pres sure you need to apply to the tool. Second,
the harder the material, the slower the speed.
Here are a couple of tips for drilling in metal.
Lubri cate the tip of the bit occasionally with
cutting oil except when drilling soft metals such
as alu minum, cop per or cast iron. If the hole to
be drilled is fairly large, drill a smaller hole first,
then enlarge to the required size, it's often faster
in the long run. Main tain enough pressure to
assure that the bit does not just spin in the hole.
This will dull the bit and greatly shorten its life.
Drilling Masonry
Soft materials such as brick are relatively easy to
drill. Concrete however, will require much more
pressure to keep the bit from spinning. Be sure
to use carbide tip bits for all masonry work.
20
Operating Tips
Before using an accessory,
be
certain
that
SAVE THESE INSTRUCTIONS
Sanding and Polishing
its
Fine sanding and polishing re quire "touch".
Select the most efficient speed.
When using polishing bonnets, always be sure
the excess string that secures the bonnet is
tucked well within the bonnet during operation.
Wire Brushes
Work with brushes requires high speeds.
Brushing Pressure
1. Let the tips of a wire brush do the work.
Operate the brush with the lightest
pressure so only the tips of the wire come
in contact with the work.
2. If heavier pressures are used, the wires will
be overstressed, resulting in a wiping
action; and if this is continued, the life of
the brush will be shortened due to wire
fatigue.
3. Apply the brush to the work in such a way that
as much of the brush face as possible is in full
contact with the work. Applying the side or
edge of the brush to the work will result in
wire breakage and shortened brush life.
CORRECT: Wire tips doing the work.
INCORRECT: Excessive pressure can cause wire breakage.