Box Joint With a Dado Set

[Thomas McCurnin]

I prefer using a router because I made a small special use router table for box joints with a trim router permanently attached and with a quarter inch bit also permanently attached. I dialed the whole thing in for quarter inch box joints once and now store it. When I need a box joint, I can plug this thing in and have box joints in a minute. If you have the time and dough to possess a single function table and router. I bought a used trim router off Craigslist.

Box joints on a table saw involve much calibrating the size of the dado with shims and spacers, moving the dado stack up and down to get the right length of the pin, and then calibrating the fixed pin, and then moving the sled with the pin to and fro until a perfect joint is obtained. Then clamp or screw it in place. Then cut your joints. That whole process can take me 45 minutes with endless pieces of scrap to get right.

My router table and router and bit are ready to go within a minute.

[Jay Rasmussen]

Done both but table saw is much easier for me.
If you like Incra you should check out their I-Box jig. I started with a couple home-made jigs but this is really sweet. Used it many times.

[John TenEyck]

I mostly use my router table because the cuts are perfectly flat in the bottom with no little score marks in the corners. I use an Original Incra Jig which makes it easy to do a stack of parts at once and get precise indexing with the jig. I suppose I could mount the Incra Jig on my TS as well, now that I ponder it a little. I would have to cut a lot more finger joints than I do, and it's my prefered plywood drawer joint, to justify buying the Freud dado stack. My regular dado stack works fine, just leaves those little score marks in the corners.

John

[Rick Potter]

I like my Freud box joint set so much I am buying another RAS to put it in for drawer joints and quick dados.

I sold one a year ago set up for that, and have regretted it since. Don't want to mess with my other RAS to do these things, and fortunately I have room for it. To save space, I plan to cut the table down to the size of the base and use adjustable tables alongside for longer pieces.

[Charles Lent]

I've made a lot of box joints over the years, using many methods and jigs. Some years back, when the Incra I-Box jig became available, it's inventor (a friend and club member) gave me a demonstration of it's features, and I had to have one. Using it on a router table cut the joints well, but I was not happy with the tear-out, because the spinning bit is cutting both forward and back at the same time, so a sacrificial backer (zero clearance insert) isn't easy, since it needs to be on both sides of the work.

Cutting them on a table saw with the blade always cutting in the same direction through the wood only requires a sacrificial backer on the side of the work where the blade exits, and this sacrificial backer is an included feature in the I-Box jig. You just position it to an uncut area of it when about to begin cutting a new size joint. The first cut makes the required zero clearance cut through it and can be used over and over as long as you don't change the blade height or the blade set width. This sacrificial strip is just a piece of 1/4" thick MDF, so replacements can be made easily, using the original as a template, but it can be used many times and then inverted and used many times again before it actually needs replacing.

I have the Freud XBOX-8 blade set for 1/4 and 3/8" box joints, and also a Freud Ripping Blade with a 1/8" flat bottomed kerf cut, that I use these for most of my smaller box, box joints. For large boxes and larger box joints I use a Freud Dial-A-Width blade set. It has the bat ears, so doesn't make perfect box joints, but in larger boxes and joints they are less visible and so are acceptable to my needs.

I've tried many ways, even own a Leigh D4R dovetail jig and special box joint top plate, but I get better box joints with less tear-out by using the blades and jig above on my Unisaw. Attached are a few photos of some of my box joints. After buying the I-Box jig, all of my DIY single size box joint jigs went into the burn pile. Some worked great, some not so great, but the I-Box Jig is easy to adjust for different sizes and does a better job. It takes up less shop space than that stack of DIY Box Joint jigs too. It's so convenient to use that every box gets made with box joints, unless dovetail joints are a design requirement for the project.

Charley