Dadoes on the Table Saw

Cutting Dadoes on your Table Saw really, is a must have skill for woodworkers. There are so many places that you're gonna use this, from boxes to drawers, to cabinet carcasses. You gotta understand this process. So, this video article is gonna take you through, some tricks that I've learned to cut corners a little bit, and make a good fitting Dado, much easier for you to attain. Also give you information about some math you need to do, how high to set the blade, the ins and outs of getting Dado set up on your Table Saw.

So, after the dado is put together, you have a rock-solid joint, that's gonna last a really long time. Here's what you gotta have on hand, in order to do dadoes on your table saw. First, we're gonna use a Dado Head. So, I've got just, some components of my dado head, set out here. This is what's called a Stackable Dado.

What that means is, two Rim Blades. They're gonna be on the outside. We're gonna build them up, to the right width, by using what are called Chippers, on the inside. Now, sometimes we get the chippers and the rims going. We still don't have quite the right size that we need.

So that's what these are all about. This is a set of Dado Shims. These are available in a lot of different configurations. The bottom line is that, each different color, is a different thickness. So, when we add these in between our chippers and rim blades, it allows us to hit different dimensions on the dado head itself.

Next thing is a Short Made Device, and this is really where the rubber meets the road to make this process easier. This is a Short Made Jig I use. It's got all these different dadoes cut into it, and each dado has a number in it. So, starting down on the end, closest to me, I put a 23/30 seconds dado head together, made a cut. Added a five thousandths dado shim, made a cut.

Added ten thousandths, fifteen thousandths, all the way up until I hit three quarter inch. That's up here. Then I went over three quarter by five thousandths, over three quarter by ten thousandths. You need to make one of these up with your dado head. And I'm gonna show you in just a little bit, how we're gonna use this thing.

Laying on top of the short made jig, is that little piece of brass. This is Bar Stock, and I rarely take measurements, If I can avoid it. You're gonna see me use this to set the height of the dado head. For your table saw itself, you need a Dado Insert. Once we build that head up, to the right width, it's no longer gonna fit through the conventional insert, your regular saw blade goes through.

So, we've got to have a dado insert., that's got a bigger slot in it. Then as we push the material, in order to hold it securely down to the table, you're gonna want a push pad, nice neoprene pad on the bottom of that, that'll do a great job of gripping the material. That's the kit, in order to get you set up, making dadoes, in your shop. Here's the easiest way, to get quickly dialed in, on the width of the dado. This is something that, I developed over time, and man, does it save me a lot of time.

Take that short made jig, the plywood you're gonna cut the dado for, and, just put it into these test slots, until you find one that it fits. Wouldn't go into this one, scooch right into this three-quarter inch slot. That's a really, really good fit. What that tells me, is that three quarter inch, is the right width of dado, for this material. Now we're ready to build up, rim blades and chippers.

In order to make this happen, I raise up my Arbor a little, make it easier for you to see. Saw is unplugged. Rim blade goes on first. Remember that, the rim blades, have a distinct left and right side, commonly, it says on the rim blades, this side, out. Make sure that you follow the roadmap there.

In order to get three quarters of an inch, I'm gonna need six layers, cause each of these layers, is an eighth of an inch. So, I got an eighth out of the rim blade, another eighth out of that chipper. Another eighth out of this chipper. As I put everything on, I'm being really careful to make sure that, the teeth don't touch each other. Cause when we tighten up the Arbor nut, if you have carbide against carbide or carbide against steel, you'll pop a tooth off, just like that.

Another eighth inch chipper, one more of those. That final rim blade is last. Now it is possible, to get everything on here, backwards. You wanna make sure that, with any blade going on the table saw, the teeth are pointing toward you. Another final check here, in order to make sure that, no teeth are touching.

Now, when I lock this on, if I put on the Arbor Washer, there's very little Arbor sticking out, for me to get the Arbor nut on. So, on my saw, I need to leave the Arbor washer off. And only use the nut. Hang tight. One more look, then, I can make it wrench tight.

That gets us set up and we think that's right. We don't know for sure, it's right. Gotta do test cuts first, but this is as far as we're gonna go for, right now, until we know that everything on here, is just perfect. Before we can actually plow a test cut into our plywood, we need to set the height of the blade, cause that's also one of the things, we wanna make sure is right. I set the height of the blade to one quarter inch, that's one third, the thickness of the material, I'm cutting into.

The way I do that, is with bar stock, which I find much easier, than trying to measure this with, a ruler. With the bar stock on here. Saw is unplugged. I'm setting the height of the blade, until the tooth, at the top of its rotation, is even with, the top of the bar stock. And I'm gonna lock that height in place.

Position the fence in a random spot. It doesn't really matter where it goes, for this test cut. We're ready to go. What you'll see me do here, once we're powered up, is use the push pad to provide down pressure, a little bit off to the side of the insert here, so that I can pass over the dado head, but you never wanna push directly, over the cutter. I wanna be off, to the side.

So, I'm ready to plug in, and then we can make this cut. once that cut is complete, two things we wanna look for. Bring your bar stock back, and by dropping that into the dado, you can feel across the top of the bar stock onto the top of your material. If there are any disparities there, you need to adjust the height of the head, up or down, until these flush up with each other. The other test is, is the width of our head where we want it to be.

So, I bring, so, I bring my material over, drop it into that dado, in order to see, if I have a fit. And if I don't have a fit, maybe you're gonna have a fit. But, look at how easy, that Gauge Block made this. This is first set up, first cut, first fit. What I'm looking for, is, you should not have, to drive this piece into the dado.

It slipped right in, with hand pressure. Now in the same vane, when I pick up the shelf piece, this, which would be my, say my carcass side, comes with it. There's enough friction between the two, that it's holding them together, under its own pressure. So, I got a really good fit out of this on the first run. If you don't have a good fit, you're gonna need to make an adjustment to the dado head.

Typically, at this stage, this is where you're gonna pull in, your dado shims. If you find that, the fit is too tight, you've gotta expand, the stackable dado head. So, you would have to insert a shim. If you find that the fit is too loose, then the dado head is already too big. What you may have to do, is take out a chipper and add a dado shim.

So, at that point, it's a little bit of trial and error, in order to customize the fit, for your particular piece of material. But that short-made gauge block, is gonna get you a lot closer on the first try. Using the bar stock to set the height of the dado, is gonna get you a lot closer to the perfect height, on the first try. This is a skill, you really need to master, cause dadoes are just indispensable, in so many different woodworking projects, in your shop.