Building A Box Joint Jig

If this is your first visit, be sure to check out the FAQ by clicking the link above. Instead, I use a rabbet joint and screws to assemble the boxes and homemade” handles which are screwed onto each box. I simply lined up the edge of a finger with the outside edge of the blade and locked down the fence. If you keep a sample of a successful test cut as a template you can totally repeat an identical set of box joints in the future, especially useful with the INCRA HingeCrafter where you need exactly the same size box joints for every hinge of the same size in the future. Once everything was dialed in I slid the rip fence up against the right side of the jig.

In that I mean with a simple butt joint in wood your side is your side, but this joinery uses up some of that stock material in it’s nesting nature. What your looking for, is a position to put your body in as your cutting that keeps the blade moving in the right angle. For best results the expensive devices such as the Leigh Jig and the WoodRat are streets ahead of the basic jigs, but their cost is also on a different level. To get the best possible cuts, be sure to mount your saw with a high-quality blade and always check to be sure that the blade is perfectly square to the saw base. Create doll furniture to accessorize a dollhouse or make beanbags for tossing games.

Finger joints are perfect for box joinery, case construction without dovetails, shop furniture, and more. Raise the blade to the thickness of your box material—in this case, 3/4 inches—or go a hair deeper if you’d like to sand the pins flush later. I also cut a wide variety of dados for various purposes, changing blades on a table saw is just part of using one. The slots should be made on the inner side of the joint (as seen on the image.) This makes the slot hidden when you assemble the box. I set blade height to just over ¾-inch, the thickness of the stock being machined. I have developed a new box joint jig that is ideal for beekeepers who want to make their own boxes.

Note If you have a jointer, it would be best to make a few passes on the board edge before ripping. The easiest methods include using a sliding jig and a table saw, a portable router and a template-style joinery jig, or a router table and sliding fence jig or dedicated box joint router bit. A table saw is going to be much faster than using a CNC, and if you are doing this as a production run, that would be my first choice.

With most basic jigs the finger joint templates have to be bought as an accessory. The settings are simple but there is a lot to remember so be very careful and dont turn the saw on until you have double and tripple checked the distance between the blade and the metal spacer bars. Use stainless screws and hand rubbed oil finish to make your hives ONE OF A KIND show pieces with Copper Garden covers! Box joints look and work best when the width of the joint is divisible by the width of the individual joint fingers.

Most DIY box joint jigs I saw are based on one thickness of the finger joint and since the registration pin was made of wood, it eventually would wear down and make later joints less accurate. It would also avoid tear out from rounding over the edges on a router table after construction, which is nice if I choose to do that. I quicly found out that the bar that comes with the jig was too big for the miter channel on my Skill table saw but fit fine on the Bosch and incra only makes the bar in one size.

To that end, I just might make up a molding plane that shape, build the sides oversize, and plane them to finished length. I use the same jig for short and long sides of the boxes by installing a couple of spacer blocks when I do the short sides, as shown in the pictures below. I have made setup blocks or templates for anything I do more than once, then it is an easy decision to add some feature that you have the setup in the template box already to go, don’t reinvent the wheel so to speak. Either way, make sure to use a stopper” so that every piece is exactly the same.


With a series of evenly sized pins and notches spaced along the length of a corner, box joints form simple but attractive exposed connections. When I cut joints I mount 1 to 4 portable circular saw blades on the arbor (saw blade width less than joint so each joint cuts in two passes) To set the caliper I cut part way into a scrap and then use the inside caliper to set the pin width. If the box is for a graduating senior and will have a image of her in her cap and gown in the center, black or the school colors might be excellent options.

Ideally, your test cuts should be made with the same wood you’ll be using to build your box. Box joints are really a type of dovetail joint (historically, dovetail” has been used to describe both joints), but with straight sides instead of angled. The astute observer will notice that the jig is a pattern of one box joint that we will simply repeat over and over in order to cut the successive joinery.

I undersize the stuck out part of my pin a little to make it a bit easier to get the box parts on and off it. I just sand the pin a little after it is put together. After running the dado, simply relocate B so that the first dado is now on the key and run the dado after removing A. Glue up took more time than the milling and if you have a single big project, or plan to make many more boxes then I think it is worth it rather than make your own jig.

I haven’t tried the jig on the router table yet, but the how-to of that is fully covered in the Incra video so I will be giving a try. I would have preferred it if Incra could have made the front/back blocks about a tenth of an inch taller to completely allow for box joints in 3/4 inch material without risking a cut into the jig itself. For example, the pin for this jig is 3/8-inch-wide so the gauge block was cut to exactly ¾-inch wide. It would be best to make a template that you could use with the router out of the table.

I mounted my Freud SBOX8 Box Cutter blade set on my saw, with it set up for 3/8 inch grooves, got the jig adjusted just like Incra said to do in the instructional video, and proceeded to cut my test piece. When I first started out I did not have a dado blade myself so I stacked regular blades together and it worked. With the jig still attached to the miter gauge, move the table saw rip fence so it contacts the right side of the jig and lock it down. When you’re ready, disassemble the box and spread a thin layer of glue into each groove.

STEP 4: Glue and clamp a short length of 1/2″ x 1/2″ stock into the slot you’ve just created to finish the fence jig (Photo 4). This small piece is the exact size of your joint slots, and will act as an index key on which to register your workpiece as you make the cuts. To do this, simply loosen the nut that allows the base to swivel for angled cuts and place a square besie the blade. Simply place the jig on the edge of your board and mark the screw locations with your pencil.

One more joint that needs to be thoroughly tested is a 90 degree lockmitre joint, which is quick to make, strong, has lots of glue area, and leaves almost zero end grain-exposed. On my very first cut, the fingers (pins) were too small and the joint was sloppy, but not exceedingly so. After a single adjustment (following the printed instructions), the following joint was flawless. Incra has a great reputation, so when I say their I-BOX jig on their web site, it immediately caught my eye.

I started by filing a nail into an oval shape and rotating it until the joint was almost perfect but I found that the nail would flex under sideways pressure and and the joint fit was affected. The butt joint can be strengthened by fitting a block of timber within the corner either just glued or secured into each side. My personal favourite is the WoodRat, but if you want to cut exotic halfblind finger joints the Leigh Jig is the one. And, in order to do that we have to set the saw blade slightly above the thickness of the wood. You can make finger joints or dovetails with your saw and chisel… but make sure the chisel’s sharp.

If after cutting a test the fit of the box joint fingers is not exactly as you would like them you just follow the directions and move the fingers slightly one way or the other, mostly I get it right to begin with so don’t have to bother. Before you start forming the fingers, keep in mind that consistency plays a key role in making box joints that fit together well. Make sure to have an axillary fence or scrap of wood clamped to the fence for this operation. Move the fence over the exact width of the dado set, attach it to the sliding miter gauge, and cut another notch.