exact diameter. They can cut on the edge of a block of wood to cre- ate channels, and can also be used to create overlapping holes. Forstner bits require a lot of force to drive them into the wood, so they’re typically used in a drill press. These bits also have no method of clearing wood chips, so they should be retracted periodi- cally to clear the hole.
STEP BITS Cone-shaped with a “staircase” profile, step bits can drill a wide range of hole sizes with a single drill bit. Step bits can bore metal, wood, plastic and PVC. Look for a step bit that automatically deburs the holes as it drills—a nice feature because burring can sometimes be a problem with standard step bits.
AUGER BITS Auger bits are great for boring deep holes to install plumbing or electrical lines. Because they’re intended for deep drilling, they feature a long, deep spiral flute to effectively remove chips. A common 7-inch auger bit can drill through three 2x4’s, although some versions, called ship augers, range in size up to 18 inches.
Cone-shaped with a “staircase” profile, step bits can drill a wide range of hole sizes with a single drill bit. The Milwaukee SHOCKWAVE Impact Duty Electrical Step Bits are engineered to deliver best-in-class performance in impact drivers with the versatility to be used in drills. Photo © Milwaukee Tool.
The Bosch Daredevil Auger Bits feature dual cutting edges for easy nail cutting and balanced drilling. Photo © Bosch.