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TWIST BITS: Available with straight and
reduced shanks for wood and light duty
metal drilling. High speed bits cut faster
and last longer on hard ma terials.
CARBIDE TIPPED BITS: Used for drilling
stone, con crete, plaster, cement and other
unusually hard nonmetals. Use continuous
h e a v y f e e d p r e s s u r e w h e n e m p l o y i n g
carbide tip bits.
Drilling Wood
B e c e r t a i n w o r k p i e c e i s c l a m p e d o r
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
t h a t i s l i k e l y t o s p l i n t e r , s u c h a s t h i n
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
T h e r e a r e t w o r u l e s f o r d r i l l i n g h a r d
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
e a s y t o d r i l l . C o n c r e t e h o w e v e r , w i l l
require much more pressure to keep the
bit from spinning. Be sure to use carbide
tip bits for all masonry work.
Best performance drilling in masonry is
achieved when in drill and hammer mode
(GSB18V-1330C model only).
B e f o r e
u s i n g
a n
accessory, be certain
that its maximum safe operating speed is
not exceeded by the nameplate speed of
the tool.
Do not exceed the recommended
wheel diameter.
Sanding and Polishing
Fine sanding and polishing re quire “touch”.
Select the most efficient speed.
When using polishing bonnets, alway 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.
Operating Tips
CORRECT:
Wire tips doing the work.
INCORRECT:
Excessive pressure can cause wire breakage.
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