Cut Accurate and Clean Rabbets


By Christopher Schwarz
From the Spring 2004 issue of Woodworking Magazine, pages 8-11

When I was taught to cut rabbets in my first woodworking class, we made them with two cuts on the table saw. You’ve probably seen this technique in books and magazines before. For the first cut, the work is flat on the table. For the second cut, you stand the work on edge and press it against the fence as you move the work over the blade. The waste falls away and your joint is complete.

I’ve always struggled with this technique. It never seemed to produce a perfect rabbet every time. The technique does have its strengths: Most woodworkers have a table saw and a rip blade to make the cut; when it works, it does produce a nice smooth joint. But after years of doing it this way, I concluded that this technique has several serious weaknesses:

  • Standing the work on edge requires a tall rip fence, perfect balance on your part and a zero-clearance insert in your saw’s throat plate.
  • The joint is time-consuming because it almost always requires two saw setups and several test pieces to get it just right.
  • You have to move the saw’s guard out of the way for the second cut, no matter which brand of guard you have on your saw.

So we decided to look for a better way to make rabbets. We found two good methods. The first uses two scraps and a dado stack. The second is an improved two-step process that’s virtually foolproof. But before we get to that, a quick explanation on why other methods aren’t as great.

Rabbets by Hand Take Great Skill
Rabbets are one of the first joints woodworkers learn. Try building any sort of cabinet or shelf without it and you’ll know immediately how essential this simple open trench is.

The perfect rabbet should have square shoulders and a flat bottom. And the cut should be smooth. You shouldn’t see marks from the tooling on the joint except on close inspection. If any of these elements of the joint are off, you can be in trouble at assembly time.

If the joint’s shoulders aren’t square, you likely are going to have an ugly gap between the rabbeted piece and its mate. Or worse, you will close the joint but the case will not be square. If the cut is rough, has burn marks or is inconsistent, it will be difficult to completely close the joint with clamps. Plus, a rough rabbet isn’t going to be as good a glue joint as a smooth one.

Before power tools, woodworkers made rabbets with hand tools, such as a rabbeting plane. I’ve done it this way, and it works great – once you master a couple of skills. Before you can cut this joint with a rabbeting plane, you need to learn to tune the tool and sharpen the iron. This is no small feat for a beginning woodworker. Then, once you have a tool that works, there are two settings that are paramount: the depth stop, which limits how deep the rabbet is, and the fence on the side, which controls the joint’s width. With these two set, you then make passes until the tool stops cutting – then your joint is complete.

I consider this a technique that’s best for the hand-tool enthusiast; it does take some skill. Most woodworkers are going to opt for an electron-eating solution with an easier learning curve, such as with the router or table saw.

An accessory fence on your table saw’s rip fence allows you to make perfect rabbets with one machine setup and almost always in one pass.

Routers Aren’t for Everything
The router table was my first choice for a couple of reasons: Router cuts are exceptionally clean and maintaining the squareness of the joint’s shoulders is no problem.

But after cutting a lot of rabbets on my router table, I concluded that routers are not the best choice for all-around casework rabbeting. It sounds like blasphemy, but here’s what I concluded: Most routers actually are quite underpowered for the job, so you end up cutting your projects’ joints in small, time-consuming nibbles.

A 11⁄2-horsepower router does not deliver the same sustainable torque that a 11⁄2-hp contractor saw does (no matter what the tool’s label or packaging says). Part of the problem is marketing hype among the router manufacturers, and part of the problem is in the way a universal router motor is built compared to a traditional induction motor on a contractor saw. The bottom line is this: Ask a typical router to hog out a 3⁄4″-wide x 3⁄8″-deep rabbet in one pass and it will bog down or even stall in the cut.

A router also is noisier than a table saw, and large cabinet pieces become unwieldy when you try to maneuver them on the router table. You could cut smaller rabbets on small pieces on the router table (drawers are about the right scale for most router tables). But here’s how I feel about that: Learn the rabbeting process on one machine and then do it over and over the same way so you become an expert at that process. Jumping around from technique to technique will only slow your progress as you learn the subtleties of each.

Some people use their jointer and its rabbeting ledge to cut this joint. The jointer is a powerful machine, and this technique actually works pretty well for narrow stock such as face frames and door parts. But try to rabbet the end of a 30″ x 20″ cabinet side and you’ll see why this isn’t the way most people prefer to cut rabbets.

So I went back to the table saw, which has guts galore and a big table, to see if I could find a different way to skin this wily animal.