Skil DP9505-00 Manual Del Propietário página 27

General Drilling Guidelines
WARNING
Drilling speeds
Important factors when determining the best drilling speed:
Type of material
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Size of the hole to be drilled
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Type of drill bit or cutter
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Desired quality of the cut
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Remember, smaller drill bits require greater speed than large drill bits. Softer materials require
greater speed than harder materials.
Drilling metal
Use metal-piercing twist drill bits.
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It is always necessary to lubricate the tip of the drill with oil to prevent overheating the drill
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bit.
All metal workpieces should be clamped down securely. Any tilting, twisting, or shifting
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causes a rough drill hole, and increases the potential of drill bit breakage.
Never hold a metal workpiece with your bare hands. The cutting edge of the drill bit may
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seize the workpiece and throw it, causing serious injury. The drill bit will break if the metal
piece suddenly hits the column.
If the metal is flat, clamp a piece of wood under it to prevent turning. If it cannot be laid flat
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on the table, then it should be blocked and clamped.
Drilling wood
Brad point bits are preferred. Metal piercing twist bits may be used on wood.
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Do not use auger bits. They turn so rapidly that they lift the workpiece off the table and whirl
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it around.
Always protect the drill bit by positioning the table so the drill bit will enter the center hole
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when drilling through the workpiece.
To prevent splintering, feed slowly when the bit is about to cut through to the backside of the
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workpiece.
To reduce splintering and protect the point of the bit, use scrap wood as a backing or a base
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block under the workpiece.
Feeding the bit
Pull down on the feed handles with only enough force to allow the drill bit to cut.
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Feeding too rapidly might stall the motor, cause the belt to slip, damage the workpiece, or
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break the drill bit.
Feeding too slowly will cause the drill bit to heat up and burn the workpiece.
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To reduce the risk of injury, make sure the chuck key is removed from
the chuck before starting any drilling operation .
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