Biscuit Joinery Basics

Six simple steps to make perfectly aligned joints using a biscuit joiner.

Biscuiting basics

A biscuit joiner (also known as a plate joiner) cuts half-oval slots in mating workpieces; then you glue in a football-shaped "biscuit" and clamp the joint tightly. (Common biscuit sizes are shown at left.) Biscuits add strength to joints and assist you in aligning workpieces. Here's how to set up a joiner to cut a typical joint.
Step 1

Mark biscuit-slot locations across the joint between two boards you want to join. Mark the first board, then transfer to the second.
Step 2

Set the plunge-depth adjuster to match the biscuit size. For maximum strength, use the largest biscuit that fits your joint.
Step 3

Line up the slot-centering marks with your layout line. (Similar markings are on the base's bottom for using it vertically.)
Step 4

Typically, you'll center the slot in the wood. The joiner's base, when sitting on a flat surface, is preset to center the cut in 3/4"-thick stock.
Step 5

Finally, grip the joiner by the bale and the barrel (or handle), engage the power switch, and plunge the blade into the wood.
Step 6

After you've cut mating slots in your workpieces, add glue and biscuits and clamp the joint.