Skil DP9505-00, Руководство пользователя

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General Drilling Guidelines
WARNING
To reduce the risk of injury, make sure the chuck key is removed from
the chuck before starting any drilling operation .
Drilling speeds
Important factors when determining the best drilling speed:
•
Type of material
•
Size of the hole to be drilled
•
Type of drill bit or cutter
•
Desired quality of the cut
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.
•
It is always necessary to lubricate the tip of the drill with oil to prevent overheating the drill
bit.
•
All metal workpieces should be clamped down securely. Any tilting, twisting, or shifting
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
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
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.
•
Do not use auger bits. They turn so rapidly that they lift the workpiece off the table and whirl
it around.
•
Always protect the drill bit by positioning the table so the drill bit will enter the center hole
when drilling through the workpiece.
•
To prevent splintering, feed slowly when the bit is about to cut through to the backside of the
workpiece.
•
To reduce splintering and protect the point of the bit, use scrap wood as a backing or a base
block under the workpiece.
Feeding the bit
•
Pull down on the feed handles with only enough force to allow the drill bit to cut.
•
Feeding too rapidly might stall the motor, cause the belt to slip, damage the workpiece, or
break the drill bit.
•
Feeding too slowly will cause the drill bit to heat up and burn the workpiece.