Expert: Jamie Yocono - 8/31/2006

Question
Hi Jamie,
My question,... I'm sure I,ve heard somewhere that it is illegal to use a dado blade in this country,...(England)? This has been putting me off looking for such a blade,... though watching Norm Abrahms of Yankee Workshop fame,... it seems to be the easiest and logical way to go?
I am a novice in woodwork. I own a Ryobi small tablesaw,... should I be venturing down this path?
Regards D Scorer

Answer
Hi -

I've been doing woodworking a long time, and I've never heard that dado blades are illegal in England. Are you pulling my leg?

Regardless, let me give you my opinion about dado blades. A bit of background first...

There are basically two types- the stacked blade set, and a wobble blade.  With the stacked set, you're given two outside blades that look like regular sawblades, and then some cutters, that are used in between the outside blades. All of these are basically 1/8" thick, so you stack up the number you need, based on the width of the dado you want to cut. If you want a 5/8" dado, you would use the two outside blades, and 3 inside cutters. Stacked together, they will total your dado width. Included in a stacked dado set are a few "shims" in case you need to cut an odd sized dado. Add a shim to the stack and you'll have an infinite range to your dado widths.

The wobble blade works on a completely different principle, and I'm not quite sure how to explain it. It's an odd looking blade, with a dial in the center around the arbor hole. There are various dimensions stamped in the metal, and you "dial" in the dimension that you want to cut. When you do this, it adjusted the amount of run-out that the blade has, thus cutting a wider path. When set for a wide dado cut, this blade "flutters" on your saw arbor, so there's a fair amount of vibration. The good part about it is that it allows you to cut really odd sizes dados, you can "dial" up any width you want. The bad part- the wobble of the blade seems unnerving to me, it's a little scary with all that vibration. There can be a good deal of chip-out with this blade, especially with a cross cut dado. Dados that cut along the length of the wood do not chip out nearly as much.

My opinion of dado blades? Well, I have both sets, and from time to time I use them, especially if I have many dados to cut. For example, I recently needed to build two dozen drawers, and that meant 96 pieces of drawer material with a dado for the drawer bottoms. In a situation like that, a dado blade is great. Personally, I like the stacked set better than the wobble blade. It gives a better cut, with a flat bottom and crisp sides. The wobble blade tends to have a crown in the top of the cut- it's small and hard to see, but it's there.

My big beef with dados? Chipping. No matter what you do, you're going to have some chipping. It is TERRIBLE with a wobble cutter, and a little less bad with stacked cutters, but it's still prevalent. Forget the tips that the pros tell you about, including Norm. Tape doesn't help that much, and sometimes when you pull the tape off, the wood splinters and comes off with the tape. To me... it's not worth it to use dado cutters, unless you're cutting them with the grain. I rarely use a dado cutter for any cross grain cuts.

My suggestion to you - since you said they're illegal.... is to set yourself up with a nice router table and a good router. You'll get a much nicer cut, virtually no chipping, and you won't be breaking the law. In fact, you might be able to do something as simple as mounting a router to a nice flat piece of plywood or MDF, and then lay it across the fence rails of your table saw. If you're lucky, clamp it in place and use the tablesaw fence as the fence for your router table. I was in a jam at a jobsite once and did that, it worked decently for some emergency dados I had to cut.

Otherwise- my suggestion is to invest in a good router table/router combo and forget about dado blades. They're problematic, expensive, and frankly, not worth the problems that they cause. If you just have a few dados to cut, you're better off just cutting them with your tablesaw, moving the fence over bit by bit. It takes a while, but it's accurate, with virtually no chipping. If you have a lot of dados to cut, consider doing them with a router.

OK, good luck, I hope this helps. Please feel free to write back if you have any further questions after reading this.

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV
www.wooditis.com