Skil HD182001 Manual Del Propietário página 13

bit from cutting and cause excess friction by sliding over the surface. This can be damaging to
both the tool and the bit.
Drilling with Variable Speed
The variable-speed feature eliminates the need for center punches in hard materials. The
variable-speed trigger allows you to slowly increase the rotation speed. By using a slow
starting speed, you are able to keep the bit from "wandering". You can increase the speed as
the bit "bites" into the work by squeezing the trigger.
Drill Bits
Always inspect drill bits for excessive wear. Use only bits that are sharp and in good condition.
TWIST BITS: Available with straight and reduced shanks for wood and light-duty metal drilling.
Twist bits may overheat unless pulled out frequently to clear chips from flutes.
HIGH-SPEED BITS: CUT faster and last longer on hard materials.
CARBIDE TIPPED BITS: Used for drilling stone, concrete, plaster, cement, and other
unusually hard nonmetals. Use continuous, heavy feed pressure when employing carbide tip
bits.
Drilling Wood
Be certain that the workpiece is clamped or anchored firmly. 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
pressure you need to apply to the tool. Second, the harder the material, the slower the speed
you should use. Here are some tips for drilling in metal:
Lubricate the tip of the bit occasionally with cutting oil, except when drilling soft metals such
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as aluminum, copper, or cast iron.
If the hole to be drilled is fairly large, it's often faster in the long run to drill a smaller hole
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first, then enlarge it to the required size with a larger bit.
Maintain enough pressure to assure that the bit does not just spin in the hole. This will dull
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the bit and greatly shorten its life.
Drilling Masonry
Use carbide-tipped masonry bits for cinder block, mortar, common brick, soft stone, and
other masonry materials. The amount of pressure to be used is dependent upon the type of
material being drilled. Soft materials require less pressure, while the hard materials need more
pressure to prevent the drill bit from spinning.
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