Skil HD529401 Owner's Manual page 18

Drilling (Fig . 10)
WARNING
with side shields during power tool
operation or when blowing dust . If
operation is dusty, also wear a dust mask .
a. Check that the direction-of-rotation selector
is at the correct setting (forward or reverse).
b. Secure the material to be drilled in a vise or
with clamps to keep it from turning as the
drill bit rotates.
c. Hold the drill firmly, and place the bit at the
point to be drilled.
d. Depress the variable-speed trigger switch to
start the drill.
e. Move the drill bit into the workpiece, applying only enough pressure to keep the bit "biting".
Do not force the drill or apply side pressure to elongate a hole. Let the tool do the work.
f. When drilling hard, smooth surfaces, use a center punch to mark the desired location of the
hole. This will prevent the drill bit from slipping off-center as the hole is started.
g. When drilling metals, use light oil on the drill bit to keep it from overheating. The oil will
prolong the life of the bit and increase the drilling action.
h. If the bit jams in the workpiece or if the drill stalls, stop the tool immediately. Remove the bit
from the workpiece and determine the reason for jamming.
There are two rules for drilling hard materials. First, the harder the material, the greater the
pressure you need to apply to the tool. Second, the harder the material, the slower the speed
should be. If the hole to be drilled is fairly large, drill a smaller hole first, and then enlarge to
the required size with a larger bit; it's often faster in the long run.
Wood Drilling
For maximum performance, use high-speed
steel or brad-point bits for wood drilling.
Begin drilling at a very low speed to prevent
•
the bit from slipping off the starting point.
Increase speed as the drill bit bites into the
•
material.
When drilling "through" holes, secure a block
•
of wood behind the workpiece to prevent
ragged or splintered edges on the back side
of the workpiece (Fig. 11).
NOTICE: Bits may overheat unless reversed
and pulled out frequently to clear chips from
flutes.
18
Always wear safety
goggles or safety glasses
Fig. 10
Fig. 11