About Drill Bits

1. Twists Bits
These have a cone-shaped cutting point and spiral shaft. Made from high-speed steel, they’re suitable for drilling into most materials including timber, metal, plastic and steel.

2. Masonary Bits
Masonry bits are characterised by the hardened tungsten carbide point on the tip that simultaneously pounds and twists into hard masonry surfaces when the drill is set to hammer mode. Drill into softer masonry surfaces, such as old brick or cement render, without hammer action, on a slow speed.

3. Brad Point Bits
Used for woodworking, the sharp point is ideal for getting the hole positioned accurately and the outer spurs cut a clean hole.

4. Spade Bits
Also called speed bores, spade bits are for timber. Traditionally large and flat, although new designs are cylindrical, they have a sharp point in the middle and cutting spurs on the edges. They work like a spinning chisel to drill large holes and remove excess timber for locks and other fixings.

5. Multi-Construction Drill Bits
These are like masonry bits but ground differently to go through softer masonry substrates like brick, marble and sandstone, and timber, cast iron or aluminium. They’re ideal for drilling one hole through different materials. Use in non-hammer mode with a slow speed.

Changing Bits
New drills have keyless chucks, so bits can be changed by simply turning the chuck. Older drills have keyed chucks, requiring a key to loosen or tighten the jaws. A handy quick-change fits into any existing chuck for specially designed drill bits with a hexagonal end to be snapped in and out.
TIP: Keep the key taped to the end of the power lead (right) to remind you to disconnect power before changing bits. Use the chuck key in all three holes around the chuck for even pressure.