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Parts & Service: 020 8988 7400 / E-mail: Parts@clarkeinternational.com or Service@clarkeinternational.com
DRILLING TIPS
• Always use sharp, good quality drill bits. The performance of your drill
is dependant on the quality of the bits used.
• After drilling material to the full depth, do not simply pull out the drill
but maintain chuck rotation to ease withdrawal.
• Reduce the pressure on the drill bit when it is about to break through.
This will prevent the drill from jamming.
• If drilling a large hole, first drill a pilot hole using a smaller drill bit.
• Always apply pressure to your drill bit in a straight line and, where
possible, at right angles to the workpiece.
• When drilling holes or driving screws into walls, floors etc., always
make sure that there are no live electrical wires in the path of the bit.
• When drilling in metal, the materials being drilled can become hot.
To reduce overheating use a suitable cooling lubricant. No cooling
lubricant is necessary when drilling cast iron or brass as they should
be drilled dry.
• When drilling metal, the harder the metal the slower the drill speed.
Similarly, the bigger the drill bit the slower the speed.
• Always start drilling at a slow speed to prevent the drill from slipping
out of the pop mark or indent, gradually increasing speed until the
optimum cutting speed is achieved whilst maintaining a MODERATE
pressure. NEVER force the drill bit into the work. This will overheat the
tip and cause it to dull very quickly.
• To prevent the drill bit from slipping when starting to drill a hole in
metal, use a centre punch to make an indentation at the start point.
• When drilling in wood, clamp a piece of scrap wood to the
underside of the material to avoid splintering.
• Always drill directly in line with the bit. Do not use sideways
movement as this may damage the drill or cause the bit to break.
• Large holes should be drilled with wood augers, flat wood bits or
hole saws.
