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This technique starts with cutting the tails first. You can then use them to accurately lay out the pin positions. Like any method of cutting dovetails, this table saw technique depends on your stock being perfectly flat and square.
While you’re milling your stock, go ahead and make a couple of test pieces as well. The test pieces will give you a chance to practice the technique and become familiar with the overall process.
LAYOUT. Once you’ve finished preparing your workpieces, you can start laying out the tails, as in the photo above. The nice thing is, you only need to do this on one end of one workpiece.
Keep in mind that you can vary the size of the tails, but the overall layout needs to be symmetrical about the centerline of the workpiece. Plus, the space between the tails, where the pins will go, shouldn’t be any narrower than 3⁄16" to provide clearance for the saw blade.
Finally, to avoid making any mistakes as you work, mark the waste areas with an “X.”
FIRST CUTS. After tilting the blade on your saw, as shown on the previous page, you’re ready to make the first cut. Start by putting the jig into position on the table saw with the fence positioned square to the blade to make the tails. Holding the workpiece against the fence, slide the jig forward to align the blade to the outside (waste side) of the first layout mark.
Next, slide the stop block against the workpiece and lock it in place. Once the stop block is set, you’re ready to make the first cuts in all your tail workpieces (photo 1 at lower left). Be sure to set the blade height to match your layout line. In fact, I like to go just a hair deeper than the overall stock thickness to be on the safe side.
Photos 2 and 3 below show you how I use a simple, cut-andflip sequence to make the four remaining cuts. You just need to make sure to hold the workpiece securely against the stop block and jig fence.
COMPLETING THE TAILS
Now that you’ve made the first set of cuts that define one edge of the outside tails, you have a good understanding of how the jig and overall technique work. You’ll repeat this process to complete the rest of the tails on all your remaining workpieces.
The nice thing is you won’t need to worry about working to any layout lines for the rest of the work on the tails. That’s going to be taken care of by a set of spacers, like the ones you see below. They’re the key to accurate tails — and tight-fitting pins, as you’ll find out later.
SPACERS. The trick is sizing the spacers. For the technique to work, the spacers must be sized accurately. The photo and drawing below shows the relationship between the spacers and the layout already completed on the tail.
SIZING THE SPACERS
When it comes to sizing the spacers, the drawing below covers what you need to keep in mind. Basically, to position the workpieces correctly for each cut, you’ll need the same number of spacers that you have full pins. In the example here, there are two full pins (the two center pins), so two spacers are required.
Sizing the width of each spacer is just a matter of starting at the center of the half pin at one edge and measuring to the center of the first full pin. Then you continue across the workpiece, measuring from pin center to pin center. You don’t need a spacer for the last half pin on the workpiece.
COMPLETING THE TAILS. At this point, completing the tail cuts starts with inserting the first spacer into the T-track, sliding it up against the stop block, and then locking the spacer in place on the fence (photo 1).
DOUBLE CHECK. To verify the correct spacer is installed, simply set the workpiece with your layout lines in place. Then just slide it up to the saw blade and double check that the blade will cut into the waste area between the tails of the workpiece.
STAY ORGANIZED. Once that’s complete, you’re ready to use the same process to make four cuts in all of your tail workpieces. One note of caution: It’s easy to lose your concentration as you repeat the cuts four times on each workpiece, especially if you’re making a big project with a lot of parts (like a set of drawers, for instance).
While the jig takes care of properly positioning the workpiece in relation to the distance from the blade, you still need to make sure you’re keeping it tight against the fence and stop block/spacer setup. Keep an eye out for sawdust building up on the jig as well, since this can also throw off the position of the workpiece.
In photos 1 and 2 above, you can see the cuts being made with the first spacer in place. Adding the second spacer results in completing the shape of the tails, as you can see photos 3 and 4 at the top of the opposite page.
After wrapping up all the cuts on all of the tail workpieces, you’re ready for a little bit of cleanup work to finish them.
CLEAN OUT THE WASTE. Depending on your dovetail layout, the amount of cleanup work may vary. So you have some options on how to accomplish this task.
If there’s a lot of waste to clear out, simply remove the stop and spacers from the jig. Then you can simply cut away the waste with the saw blade, positioning the workpiece by eye.
The thing to make sure here is that you don’t cut into any of the tails. If it’s more comfortable,
you can use a fret or coping saw to remove the bulk of the waste.
For removing small amounts of waste and final cleanup, I turn to a freshly sharpened chisel, like the one you see in photo 5. A sharp chisel helps prevent tearout as you work across the grain of the workpiece.
Start by cutting down at the layout mark. Then cut in from the end to remove small pieces of waste. Be sure to flip the workpiece over to make the initial cuts on both faces rather than just cutting through from one side.
LAY OUT THE PINS. Once you’ve finished removing all of the waste, you’re halfway to a complete dovetail joint. Now you can turn your attention to the other half of this classic woodworking joint — the pins.
You can see how to lay out the pin workpiece using a completed tail piece in photo 6 at the lower left. Here again, you’ll only need to lay out the pins on one workpiece. The spacers will position the rest of the pin workpieces properly after the initial cut is made for the first pin.
These layout marks will only be used to initially position the stop block. Plus, it helps during the actual cuts so you know which spots are the waste areas. I make sure to sharpen my pencil and make the marks as accurately as possible.
Now, using a square, transfer the layout marks for each pin down both faces of the workpiece (photo 7). I like to mark the edge, like you see in the margin again, to identify which pin I’m going to fit first. Finally, mark the outside faces of all the workpieces.
Now you’re ready to start cutting the mating pins. For more on this, turn to the next page.
FITTING THE PINS
With the layout complete, you’re just about ready to start cutting the pins. But there are a couple adjustments you’ll need to make to the jig and your table saw. The first thing to do is reset your table saw blade to 90°. Unlike the tails, the pins are cut with the blade square to the table. Instead of tilting the blade, you’ll set the angle of the jig to match the tail angle.
The last thing you’ll need to do is remove the dovetail blade you used to cut the tails. To get a flat bottom, use a rip blade. A dado blade does remove the waste quicker, but I’ve found I get the best results with a rip blade.
SIZING THE FIRST PIN. You must match the first pin with the tail piece. For the edges of the workpieces to end up flush, the first pin needs to match its mating opening in the tail piece exactly.
The process for doing this is just a matter of sneaking up on the final size. After that, completing the rest of the pins involves using the spacers.
Then you’ll do some fine-tuning right on the table saw.
ADJUST THE FENCE. Pull the indexing pin and angle the fence on the jig back to match the dovetail angle. And be sure that the depth of cut of the saw blade matches the layout line on the pin workpiece. At this point, you’re ready to create the first pin (photo 1).
CHECK THE FIT. The goal here is that the pin matches its mating tail piece. Since you can’t slide the pieces together, check the fit by comparing both next to each other, as in photo 2.