Box joints are a handy, sturdy, and stylish substitute to dovetail joints. Although dovetail joints have more strength than the box joints, it is also quite tricky to build.
However, the box joints are relatively easy to make, as you will see in the following steps with the help of your table saw. So how to make box joints? Before diving into this how to make finger joints article, you need to gather some materials.
How To Make Box Joints
When you begin making the box joint jig, you need to decide the width of each of the joints’ fingers. Suppose you want to make finger joints .5 inches wide, so you need to start ripping a strip of your stock ½” by 1/2″ by at least 4″ long.
Moreover, you need to cut a piece of 1/6 to a finished size of 5-1/2″ by 10″. The materials that you need are a power drill, either cordless or corded, stacked dado blade set, table saw, miter gauge, ¾” of plywood, 3 1-1/4″ of wood screws, and woodworking glue.
In the first step, after you have cut two pieces for your jig, you need to install your stacked dado blade set in the table saw. You have to position adequate chippers between your two outer blades so that your final width of the cut is matched with the width that you desire for the joint fingers.
Now you have to attach your board to the miter gauge of your table saw. To do this, slip your miter gauge inside the miter slot to the left side of the saw blade. Also, check to see that your miter gauge is set at 90 degrees, perpendicular to your saw blade.
Next keep the board against the miter gauge on one of your long edges. Make sure that the board is extended at least ½” past your stacked dado blade. Then use the drill to nail a couple of wood screws through the holes or slots in your miter gauge and into the piece of wood.
Make sure that the screws are short so that its point does not penetrate through the board face.
Now that the board is attached to the table saw’s miter gauge, you have to cut a notch in the board to assist a spacer block. You need to adjust the dado blade’s height to ½” above the top of your table saw if the strip that you cut earlier in the first step is ½” wide by ½” high.
Next, switch on the motor and slide your miter gauge forward by guiding your backer board the entire way via the blade, cutting a ½” by ½” notch on your board. Then slide the miter gauge back towards your direction, clearing the blade once more.
After you have cut the first notch in your backer board, enter the spacer block inside the notch. Next, slide your spacer block so that its end is 2″ past the front side of the backer board.
Mark on the spacer block with the pencil against the backer board’s backside. Now slice the spacer block at this line and keep both halves cut since you will need the pieces.
Next, turn your miter gauge upside down after removing it from the table saw. This will expose the board’s bottom side. Place a little glue inside the notch, and keep the spacer block in it so that the newly made cut is flush with its backside.
Countersink and pre-drill a screw fixing this spacer block to your backer board.
After installing the spacer block, re-position your miter gauge in the left slot of your table saw. Remove the two screws that tied the jig to your miter gauge. Shift your joint box jig a little to the right and use the remaining portion of your spacer block to adjust the width of your jig.
Now that the spacer block is precisely one joint finger’s width past your dado blade, attach your backer block again to the miter gauge with the two screws you removed previously. This completes the joint box jig.
Now to cut the box joint, you need two stock pieces. Before you make the first cut adjust the depth of your stacked dado blade on your table, saw to match its thickness.
Now position your board on the edge so that the board’s end edge that you cut will be flat on the table. Slide your panel on the right to butt up against your spacer block.
After ensuring that the board is extended square upward to your table saw, clamp it against your jig with a woodworking clamp.
After the first finger is cut, remove your clamp from the jig and position the board again so that the notch slides on the spacer block onto the jig. Cut the second notch in the same method as the first and continue the procedure until all of the finger notches on the board’s edge are cut.
Now that the box joint fingers on both the boards have been cut, you can check to see the result by assembling your box joint. After completing, the joint should fit snugly, and the fingers must extend a little past the corresponding board’s outside face.
For the final assembly, put a small amount of glue on all the box joint’s faces on both the boards, assemble your joints, and put the boards back in their places.