Skil PWRCORE 20 HD6294B-00 Owner's Manual page 17

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, then enlarge to the
required size with a larger bit; it's often faster in the long run than drilling a larger hole initially.
Wood Drilling
For maximum performance, use high-speed
steel or brad-point bits for wood drilling.
a. Begin drilling at a very low speed to prevent
the bit from slipping off the starting point.
b. Increase speed as the drill bit bites into the
material.
c. When drilling "through" holes, place a block
of wood behind the workpiece to prevent
ragged or splintered edges on the back
side of the workpiece (Fig. 12).
NOTICE: Bits may overheat unless they are
reversed and pulled out frequently to clear
chips from the flutes.
Metal Drilling
For maximum performance, use high-speed steel bits for metal or steel drilling.
a. 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 efficiency.
b. Begin drilling at a very low speed to prevent the bit from slipping off the starting point.
c. Maintain a speed and a pressure that allow cutting without overheating the bit.
Applying too much pressure will:
Overheat the drill.
–
Wear the bearings.
–
Bend or burn bits.
–
Produce off-center or irregularly shaped holes.
–
Masonry Drilling
For maximum performance, use carbide-tipped masonry bits when drilling holes in brick, tile,
concrete, etc.
Maintain a speed and a pressure that allow cutting without overheating the bit or drill.
•
Applying too much pressure will:
Overheat the drill.
–
Wear the bearings.
–
Bend or burn bits.
–
Produce off-center or irregular-shaped holes.
–
Apply light pressure and medium speed for best results in brick.
•
Apply additional pressure for hard materials such as concrete.
•
Fig . 12
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