Popular Woodworking 2003-06 № 134, страница 41

One important variant is the rabbet-and-dado joint. This is a good rack-resistant joint that assembles easily because both boards are positively located. The dado or groove doesn't have to be big; often it's a single saw kerf, no deeper than one-third the board's thickness. Into it fits an offset tongue created on the mating board by the rabbet.

The rabbet-and-dado joint is a good choice for plywood casework because it's often difficult to scale a dado or groove to the inexact thickness of plywood. It's far easier to customize the width of a rabbet. So you cut a stock-width dado, then cut the mating rabbet to a custom dimension. An extra cutting operation is required, but the benefit -a big one - is a tight joint.

There are lots of good ways to cut rabbets. The table saw, radial-arm saw, jointer and router all come to mind. The most versatile techniques use the table saw and router.

Rabbeting on the Table Saw

Rabbets can be cut at least two different ways on the table saw. Which method you choose may be influenced by the number of rabbets you have to cut, as well as the sizes and proportions of the workpieces.

It's quickest to cut the rabbets using whatever blade is in the saw. Two passes are all it takes. But if you have lots of rabbets to cut,

Single-rabbet joints

or if the workpieces are too big to stand on edge safely, then use a dado cutter. (The latter is especially appropriate if your job entails dados as well as rabbets.) Let's look at the quick method first.

The first cut forms the shoulder. To set it up, adjust the blade height for the depth of the rabbet. There are a variety of setup tools you can use here, but it's always a good idea to make a test cut so you can measure the actual depth of the kerf.

That done, position the fence to locate the rabbet's shoulder. This establishes the rabbet width, so you measure from the face of the fence to the outside of the blade.

The cutting procedure is to lay the work flat on the saw's table, then run the edge along the fence and make the shoulder cut. If you are rabbeting the long edge of a board, use just the fence as the guide. When cutting a rabbet across the end of a piece, guide the work with your miter gauge and use the fence simply as a positioning device. It is easy to set up, and the miter gauge keeps the work from "walking" as it slides along the table saw's fence. Because no waste will be left between the blade and the fence, you can do this safely.

Nevertheless, if you feel uneasy about using the miter gauge and fence together, use a standoff block. Clamp a scrap (your standoff block) to the fence near the front edge of the saw's table. Lay the work in the miter gauge and slide it against the scrap. As you make the cut, the work is clear of the fence by the thickness of the scrap. (Try using a 1"-thick block to make setup easier.)

Having cut the shoulders of all the rabbets, you next adjust the setup to make the bottom cut. You may need to change the height of the blade or the fence position. You may need to do both.

Double-rabbet joint

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Clamp a sacrificial facing - a strip of luan plywood here - to your table saw fence when cutting rabbets with a dado head. Run the cutter up into the facing, exposing only enough of the cutter to form the rabbet.

Adjust the blade to match the width of the rabbet. Reposition the fence to cut the bottom of the rabbet, with the waste falling to the outside of the blade. Make that cut with the workpiece standing on edge, its kerfed face away from the fence.

When the workpieces are so large as to be cumbersome on edge - cabinet sides, for example - you want to cut the rabbets with a dado cutter. That way you can keep the work flat on the saw's table. Control the cut using a cutoff box or the fence. It's very easy to set the width of the cut with this approach.

Where the proportions of the workpiece allow it, use the rip fence to guide the cut. Clamp a sacrificial facing to the fence. Don't fret about the width of the stack, so long as it exceeds the width of the rabbet you want. Part of the cutter is buried in the fence facing, and you just set the fence to expose the width of the cutter that's working. Guide the work along the fence.

Alternatively, use a cutoff box to support the work and guide the cut. You get the same advantages in rabbeting that you do with dadoing: The work really doesn't move, the box does. Use a stop block to position the work to yield the width of rabbet you want. On the other hand, it may be a little more difficult to get exactly the cut width you want.

Rabbeting with the Router

The router is an excellent tool for rabbeting, in part because you can deploy it as a hand tool. For some jobs, you just want to

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