Expert: Jamie Yocono - 12/6/2004

Question
I am looking for a low cost method of cutting dados in case work using a router.  Currently I use a wooden t-square clamped to the piece I am dadoing.  I would like to improve upon this method. I have seen the dado jig from Woodhaven, but wonder if there are other choices or home made jig methods.
Thanks for your help,
Jack

Answer
Jack-

While I'm unfamiliar with the dado jig from Woodhaven, I'm sure cutting dados with your own jig is probably just as accurate, as long as your T-square is perfectly square. There are only a few things that I could mention that might make your process easier, but really, it sounds like you're on the right track.

First, for ease of setup, you could make a T-square jig for each size bit that you use. You could rout a small indexing dado in the short edge of each jig, thereby indicating the exact location of the cut. Then, when you need a 3/4" dado, all you would have to do it draw a line where you need it, and line it up the dado that's precut in your jig, so that set up is swift. I've done that many a time.

That process is detailed in Patrick Spielman's Router Jigs and Techniques book, which is a good digest of router tricks. He also has a few other gems of wisdom about making a jig that gives you equally spaced dados, so if that's what you're doing, you might want to check out his book.

You can use just about anything for a straight edge- like a level, or a straight board, or there are some fancy devices that are actually made just for that purpose. I use a straight edge clamp, called an Edge-mate or something like that. (They're sold in most hardware stores in the aisle that holds all their clamps.)   But you can accomplish the same thing with a straight piece of wood and 2 c-clamps. The Edge-mate clamp doesn't particularly clamp that tightly to the board, so I add a small C-clamp at each edge of the board so that I don't have any slippage.

Another thing to ensure a good straight dado, and one where your router can't wander, is to clamp 2 straight edges, one on each side of the router base. Sometimes- with very dense wood- the router wants to wander a bit, so having the router base completely "enclosed" is a good way to protect your wood from an errant cut.

Last thing....if you gang your two sides together, you can cut the slot across both of them at the same time. Clamp the two sides together, side by side, with a bar clamp. Cut your dado across both pieces of wood.  When you unclamp the sides from each other, your slots should line up perfectly with it's mate.

You're on the right track with the way you're doing it, but it's just a little labor intensive. I did it that way for years, before I purchased a monster radial arm saw that I fit with a dado blade. It takes longer to install the blade than it does to cut the dados, but if I have a lot of them to cut, it sure it quick and easy.

Good luck, I hope this helps. Feel free to write back with any other questions you might have after reading this.

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV