How to Tell the Kind of Drill Bits Apart
- 1). Pick up several ordinary twist drill bits. Look for a chisel-like tip on the ends of each one where the surfaces of the bit come together to a flat edge instead of a sharp point. Also notice that some bits have a sharper angle of incline while others are flatter. Chisel tips with a steeper angle are better for wood and softer materials because the higher angle helps create a smooth wall in the hole of the material. Chisel tips with a low angle tip, ones that are flatter, are better for plastics and metals because the cutting surface reaches the material quicker and with more force. Twist drills make up the bulk of all bits.
- 2). Find a bit with an abrasive tip slightly larger than the body of the drill, and which has a single groove running along the body to let debris pass through. This is a masonry bit designed for stone, brick and concrete. The tip is made from more durable material, such as tungsten carbide, and is bonded to a steel body.
- 3). Locate a bit with a metal shaft and a tip that somewhat resembles an arrowhead. This is a tile bit with a ground tungsten carbide tip, available in all standard sizes. This tip is designed to cut through ceramic and glass with a tough, pointed, abrasive tip. Use a lubricant during the drilling process to cool the tip when cutting into glass.
- 4). Observe any odd looking bits that are flat like a screwdriver, but with a small extended point in the middle. Also look for ones that have a cylinder with saw teeth attached to the bit. Both are used to cut holes that are wide and smooth. The former is a flat wood bit. It cuts through wood and sheet rock or plasterboard. The latter is a hole saw that cuts wood or plastic. The flat wood bit leaves a small hole at the bottom of the cut that can be used as a starter hole for a screw in a recessed channel.
- 5). Notice another type of circular hole cutting bit with a wide, almost disc-like, cutting surface situated on the end of a standard bit. This peculiar-looking bit is called a forstner. It is designed to cut shallow holes in cabinets or in furniture.
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