Drill without damage

3 bits together
You'll need all three bit styles - twist, brad-point, and Forstner -- to drill tear-out-free holes in a range of sizes.

1. Start with the right bit

Do-it-all twist bits are inexpensive and designed to punch through wood, metal, and plastics. To achieve this versatility, manufacturers typically grind their cutting tips to 118°. This shallow angle can allow the bit to wander on entry and blow out wood fibers on exit, so reserve twist bits for plastic, metal, and holes smaller than 18 " in wood where the small size minimizes those tendencies.

For holes sized from 18 " to 12 ", instead select a brad-point bit. The center point of a brad-point bit prevents wandering on entry, while the sharp outer spurs shear the wood for far less tear-out.

When you need to drill holes larger than 12 ", move up to a Forstner bit. Like brad-point bits, Forstners feature a center guiding point and cut very clean holes. Multispur Forstner bits, like the one shown above, add sawlike teeth to the rims, which cut more aggressively without sacrificing cut quality. When using this type of Forstner, slow the feed rate, and secure the workpiece with clamps.

2. Back up your cut

Regardless of bit choice, any time you punch metal through wood, unsupported wood fibers on the back of the workpiece can tear out. So get in the practice of backing up your workpiece with scrap wood. The backing board traps the wood fibers around the exit point, preventing the bit from pushing out the last splinters. At the drill press, simply slip a scrap beneath the workpiece; for handheld drilling, clamp the backer in place, as shown below. If your bits lift fibers around the entry points, apply masking tape to the face of the workpiece before marking your layout lines and drilling.

Drilling holes on blue tape

3. Drill from both directions

If the location of a hole makes it difficult to clamp a backer board in place (such as when drilling cord-access holes in the back of an entertainment center), instead drill from both directions, as shown below, for a hole with clean edges.

Drilling hole of side of board
After drilling a 1/16" pilot hole through the workpiece, use the hole to guide the point of a Forstner or brad-point bit about halfway through.

Drilling hole of side of board with larger bit
Repeat on the opposite side of the part, again using the pilot hole to guide the point of the bit until the two larger holes meet.

3 bits together
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