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ADJUST FENCE TO SET DEPTH OF GROOVE

RAISE OR LOWER BIT TO "SNEAK UP" ON SiZE OF GROOVE

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bit size is narrower than final groove size

location of the fence. I like to make the grooves about deep.

Rout Grooves First Once everything is set up, you can make some test cuts. Then, you can verify the depth of the groove is what you want and is roughly centered on the thickness of the workpiece.

Next, I'll flip the test piece end-for-end and make another pass. This automatically centers the groove on the thickness of the piece, as in Figure 1, Now you can check the fit of the panel. You may need to tweak the height of the bit and make some more test cuts until you get a good fit. Then rout a groove on all the rails and stiles.

STUB TENONS

Now that you have the grooves cut, you can set up to cut the stub tenons on the rails to fit. What's nice is you've already determined the length of the tenon by setting the

fence for the depth of the groove. This means you can concentrate on sizing the stub tenons.

Adjust Bit Height. To do this, you can use the groove on a work-piece as a set-up gauge. I adjusted the height of the bit so that the top of the cutting edge was just shy of the shoulder of the groove, as you can see in Figure 2,

Use a Sled. To form the tenon, you'll be routing the end grain. But one of the problems with routing end grain is the likelihood of tearout. That's why I like to back up the cut with a router sled {see box below). Another benefit is it also helps hold the workpiece square to the fence.

Two Passes. If you look at the bottom two drawings on the right, you'll see that I make the cheeks of the tenon in two passes per side. That's because the slot-cutting bit isn't wide enough to form the cheeks of the tenons in one pass.

The first pass is a light cut made with the workpiece "elevated" on a '4" hardboard platform (Figure 3). Next, flip the workpiece and repeat the cut on the other side. Now, rotate the sled 180° and make a second pass on each side with the workpiece resting on the router table, as shown in Figure 4.

Once you get the hang of it, it doesn't take much time at all to make stub tenons and grooves. Plus, you've found another use for that slot-cutting bit.

Routing Stub Tenons:

Tenoning Sled

To rout the stub tenons on the ends of the rails, you need to keep the workpiece square to the router fence. And you need to make two passes on each side of the workpiece to create the tenon. This simple sled does the job.

The base is made from Vg" hardboard. On one end of the sled, the hardboard base extends out past a fence to make a platform for the workpiece. This elevates the workpiece to make the initial cut on the face to form the tenon. The fence at the opposite end of the sled is flush with the hard-board. It's used to make the final cut on each face of the workpiece to complete the tenon.

SLED FENCE (2 k 12 - %i Ply.)

WIDTH OF WORKPIECE PLUS AN

SLED FENCE (2 x 12 - ³A Ply.)

SECOND SET OF CUTS MADE FENCE

FENCE FLUSH WITH HARDBOARD

BASE (12 x 12 - Ve Hdbd.)

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