How to Cut a Corner Half Lap Joint with Hand Tools: Step-by-Step Tutorial

A corner half lap joint is an excellent starting point for anyone learning woodworking. It’s simple, versatile, and helps build foundational skills for other more advanced joints. In this step-by-step guide, I’ll show you how to cut a corner half lap joint using hand tools.

Tools and Materials Needed

Tools:

• Tenon saw

• Combination square

• Marking gauge

• Bench hook

• Chisel (preferably wide and inexpensive for beginners)

• Sandpaper

Materials:

• Two pieces of timber (e.g., 44mm x 33mm or similar dimensions)

Step 1: Marking the Face and Edge Sides

1. Inspect your timber: Look for smooth, square edges and avoid knots unless they’re part of the design.

2. Choose face and edge sides:

• Select the smoothest side as your face.

• Mark the adjacent side as the edge.

3. Label your timber:

• Use a “Face” symbol for the face side and an “Edge” symbol for the edge side.

• Repeat these markings on all visible sides.

Step 2: Cutting the Timber to Length

1. Measure and mark: Measure 220mm from one end and mark this as your cutting line.

2. Draw a line around the timber:

• Use the combination square to mark all four sides of the timber.

3. Cut the timber:

• Use a tenon saw and cut on the waste side of the line.

• Secure the timber with a bench hook while cutting.

4. Repeat for the second piece to create two equal lengths of timber.

Step 3: Marking the Half Lap Joint

1. Position the pieces:

• Arrange the pieces in an "L" shape with faces up and edges in.

• Label the pieces as "Right" and "Left."

2. Mark the overlap:

• Place one piece on top of the other and mark the width of the overlapping timber, with 5-8mm extra overhang that can be cut down or planed later.

3. Square the lines:

• Use the combination square to draw lines across the face and edges where the timber will be removed.

TIP: easier to cut more off, than trying to add more timber on!

Step 4: Cutting the Waste

1. Measure the depth:

• Use a marking gauge to find the halfway point of the timber’s thickness.

• Mark this depth on all sides of the waste area.

2. Cut the waste area:

• Use a tenon saw to make two straight cuts down to the marked depth, one on each side of the waste area.

• Make additional saw cuts within the waste area to create kerfs.

• Remove the waste by chiseling out the remaining material.

Step 5: Cleaning and Checking the Joint

1. Clean the joint:

• Use a chisel to remove rough edges and ensure a smooth surface.

• Sand the ends for a finer finish.

2. Check for fit:

• Assemble the joint and check for square alignment and flush surfaces.

• Make adjustments as needed using a chisel or sandpaper.

Step 6: Finishing the Joint

1. Final sanding and planing:

• Sand and plane the joint for a smooth, professional finish.

2. Optional: Glue and clamp:

• For a permanent joint, apply glue and clamp until dry.

Practical Uses for a Corner Half Lap Joint

This joint is commonly used in:

• Wall plates and basic structures

• Boxes and frames

• Beginner woodworking projects

Watch the Full Tutorial

For a detailed walkthrough, watch my video tutorial on YouTube: Corner Half Lap Joint Tutorial.

See many more friendly helpful tutorials on our dedicated Tutorials section on our website.
Make it a good one! Happy woodworking.