How to Make Wood Lap Joints

Woodworkers commonly use lap joints of various types in their woodworking projects.

Lap joints are made in various styles for differing applications. The basic design requires two cuts of wood that overlap. Some variations include half-lap, center lap and lap miter and they are cut using a table saw or router.

Run all wood pieces through a thickness planer to ensure uniform thickness. Be aware that using wood with various thicknesses will not produce flush cuts.

Using a test piece of wood, adjust the blade of the saw to a height that cuts exactly through the halfway point of the piece. Repeat the process as many times as necessary to attain the correct setting.

Cut a test lap joint and fit the pieces together. Run your finger across the intersection of the joint to feel for any unevenness across the joint. Adjust the blade accordingly if the face of each piece is not flush.

Start cutting the lap joint pieces by passing the wood over the blade. Do this until the correct shoulder length is met.

Examine each cut joint piece removing any excess shavings or bumps. Pieces must be flush after cutting.

Apply wood glue to each joint piece. Then clamp the joint assembly together until the glue is dry.

Things You Will Need

  • Table saw or router
  • Dado head blade
  • Thickness planer
  • Wood glue
  • Safety eyewear
  • Gloves

Tip

  • Find an illustration of a lap joint in a carpentry magazine, website or trade journal.