How to Make a Comb Joint
- 1). Lay one of the wooden planks flat on the work desk. Place the other plank in a vertical position on top of the first plank; the ends of the planks should be flush together. Using the edge of the vertical plank as a ruler, draw a line across the horizontal plank equal to the thickness of the wood. Use a marking knife to score into the wood along this line, and continue across all four surfaces of the horizontal plank.
- 2). Measure one-third of the way along the line on the horizontal plank and draw a line connecting this line to the end of the plank. This marks the beginning of the first tooth of the comb joint. Measure another third of the way along and draw an identical line. Shade the two outside segments with pencil to mark them as waste wood and prevent the wrong parts of the wood from being sawn off.
- 3). Lock the wood in a vice and use a coping saw to cut off the waste wood. This leaves you with just the tooth part of the comb joint. Line the pieces of wood up in the same way as you did in Step 1, but this time the vertical piece of wood will only have a tooth rather than a complete edge. Center this tooth in the middle of the edge of the horizontal piece of wood. Draw around it and shade it in to indicate that it is waste wood.
- 4). Clamp the horizontal piece of wood in a vice and saw around the edge of the shaded portion of the wood. Remove this waste wood and apply wood glue to the insides of the notch created. Slot the tooth of the other piece of wood into the notch and hold the two pieces together until the glue is dry. The 90-degree angle created is called a comb joint. For wider pieces of wood, you will need to cut more teeth and notches to support the joint.
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