How to Make a Dovetail Joint With a Table Saw
How to Make a Dovetail Joint With a Table Saw. It used to be that to tell a piece of old furniture from the new stuff, you had to look no further than the drawer corners. Most drawer corners built in days gone by were formed with a particularly elegant joint known as a dovetail. This joint is known for its precise mitered corners. These mitered corners and the fact that the joint does not cut all the way through the material make it impossible to cut a true dovetail, using a table saw. However, a nearly identical square tailed relative of the doevetail, the box joint, or, square dovetail, can be cut with ease.
- Tape measure
- Hardwood lumber
- Wood screws
- Table saw
- Dado blade
- Miter fence
Mark the ends of two pieces of 1-by-4 hardwood lumber (technically 3/4-inch-by-3-1/2-inch), 10 inches long, every 1/4 inch across their width at one end of each so that the lines match. These are you joint members.
Cut a third piece of stock, 12 inches long Screw this third piece, centered to the face of the a table saw miter fence, so that the wide face of the hardwood is against the vertical plate. Use a cordless drill and two 3/4-inch wood screws. (A table saw miter fence is a flat metal bar with a handle behind a vertical plate that is used to push pieces through the table saw on an angle) Set the angle to 0 or 90, so that the vertical back plate is perpendicular to the flat horizontal metal rod.
Install a 1/4-inch dado blade on your table saw and set it to a depth of 3/4-inch. Put on your safety glasses and turn on the saw. Place the metal rod in the miter fence channel in the saw table and run the hardwood through the blade, leaving a 1/4-by-3/4-inch notch in the board. Turn off the saw.
Beginning at the left edge, as you face the hardwood attached to the miter fence, mark the board every 1/4 inch using a pencil and framing square to make the mark across the height of the hardwood for clarity.
Align the joint members wide face to wide face, ends flush, so that one piece hangs off of the other 1/4 inch. Use a small C-clamp to clamp them firmly in this position.
Stand the joint members on end in front of the miter fence. Position the joint members against the face of the fence with their left edge even with the left edge of the notch you cut in the hardwood. Clamp the joint members to the fence, on the right side of the handle to avoid the blade, with a quick clamp. Use the square to make sure the pieces are square, with the two joint pieces perpendicular (upright) to the hardwood fence face. Do not release the C-clamp.
Position the miter fence on the table with attached pieces and slide it up to the still blade to check alignment. Bring it back to the edge of the table and start the saw. Push the fence through the blade, so that one joint member is notched in the overlapping edge. Turn off the saw.
Release the quick clamp and realign the joint members on the hardwood fence, 1/2 inch (two of the marked 1/4-inch lines) to the left. Re-clamp the piece, reset the fence and start the saw. Push the fence through the blade again to notch both pieces. Continue resetting and running the joint members over the dado blade until the face is notched every other 1/4 inch. Turn off the saw.
Release both clamps and align the two joint member ends. The tongues and notches will slide together, with a little force, to form a square dovetail, or box joint. To joint pieces permanently, add a small drop of wood glue in the bottom of each notch, slide the pieces together and clamp in place until dry.
- "Jim Tolpin's Table Saw Magic"; Jim Tolpin; 2004
- "Woodworking Joints"; Gordon Warr; 1989
- Wood Gears: Dovetail