Annular cutters make smooth-walled, burr-free holes in one pass. They use less power, create less torque, produce fewer chips, and drill to closer tolerances than standard twist drill bits. They do not require predrilling or step drilling. Annular cutters have a hollow core surrounded by teeth that cut through the perimeter of the hole during drilling, leaving a solid slug in the center. They also have flutes that pull chips out of the hole during drilling and a pilot pin that centers the cutters and allows coolant to flow to their tip during drilling.
Arbor adapters are required when using annular cutters with drill presses and milling machines.
- Use HSS cutters for mild steel, aluminum, soft metal
- Use TCT cutters for stainless steel, cast iron, hard metals