Completing The Joint With The Tails

It may seem like you've completed a monumental effort just getting the pins cut and cleaned up — especially if you're cutting dovetails for a whole set of drawers. But now it's time to move on to the tails.

All of the waste you just removed from the board with the pins must be filled with something . . . the tails. Before marking the cuts, however, the base line (or shoulders) must be marked, Fig. 1. Since there's a half-pin on the outside edges of the first board, there must be a complementary recess (or waste section) on the board for the tails. This means that the edges must be marked (as shown in the drawing) as well as the face of the board.

MARKING THE CUTS

The pins on the first board are used to mark the cut lines for the tails on the second board. Fig. 2. As you hold the boards in position for marking, make sure the pins (on the "IN" face of the board) are right on the base line.

In order to mark the cut lines for the tails, you should work from the inside corner formed by the two boards, as shown in Fig. 3. If you were to mark the line from the outside, the point of the pencil would naturally want to fall into the grain pattern and 'straighten out.' By going to the inside corner, the grain forces the point against the edge of the pin — exactly where you want it to be.

No matter what kind of marking instrument you use (pencil, scribe, or a rusty old nail), the marked line will always be on the 'good' side of the cut. Look at Figure 3 again. What you're marking is the waste section where the pins will reside as the joint goes together. Notice that the marked line is on the 'good' side. In other words, you'll want to leave this line.

There's another dilemma here. When marking the cut lines for the tails, you're marking on the "IN" side of the board. However, the pin will actually go all the way through to the other side (to the "out" side), and that's where the two corners must actually touch. This is why it's so important for the pins to be absolutely straight — from tip to shoulder.

marking the ends. Once all the angled Unes are marked on the "IN" face of the board, use a try square to carry them across the top (end grain) of the board. Once again, it's best to clearly mark the waste sections.

SAWING DOWN THE LINES

Now we get to the hard part. You have to

make an angled cut that just barely skims off part of the pencil line. This cut is difficult for two reasons. First, you're cutting along the "IN" side of the board — the side that won't show in the final assembly. The other side of the board (the "out" side) is what will show.

Second, the saw must be tilted to the same angle of the cut. What usually happens to me during these cuts is that I tend to saw straight down. Fortunately, this means the kerf stays on the 'waste' side of the cut. But it also means it's not where it's supposed to be. To help with this problem, I angle the board in the vice so the cut line is almost vertical.

Now, place one tooth of the saw up against the marked line. This placement will actually be taking the tiniest smidgen too much (remember the line is on the 'good' side). That's okay, because you need a little (but not too much) clearance for the joint to go together.

REMOVING THE WASTE

After you've sawn down all the cut lines, the waste can be chopped out. Here the same procedure is followed as it was for the pins: clamp the backing fence along the base line, chop (gently) straight down, and chip out the w aste.

This is where using the chisel to mark the width of the pins comes into play. When the waste is chipped out, there must be enough room to get the chisel between the corners of the tails, Fig. 6.

After chipping out the waste about %'s of the way down, flip the board over and continue on the other side, Fig. 7.

the ends. Notice the waste sections for the two half pins on the outside edges of the board, Fig. 7. Here I've chopped straight down on the base line, however, no undercutting was done. The shoulder that's formed will be visible, and you want it to be straight across.

After the waste sections in the middle of the board are chipped away, the waste for the half pins can be removed. TYirn the board on edge and chop straight down on the shoulder line (it was marked in Fig. 1). Then pare out a small V-cut, Fig. 8. Finally, saw down this shoulder line to remove the waste, Fig. 9. Since the saw cut may not be very clean, pare off the roughness with a sharp chisel. And while you're at it, go ahead and clean up the corners in all the waste sections.

ASSEMBLY AND FINISHING

Now comes the moment of truth. Position the tails over the recesses between the pins. To get even pressure across the board, place a striking board on top, Fig. 10 and tap the joint together.

You see, every joint line fits perfectly. Oh, there may be a few little places where the kerf is too wide, but these voids can be filled during the finishing stage.

The one problem you want to be careful of is the joint being too tight in some places. This will cause the wood to split. So, tap the joint together gently, checking for overly tight joint lines. If there are tight spots, knock the joint apart and pare off some of the excess from the tails.

When the joint fits properly it can be admired as it is, or glued up to finish the project you're working on. Only a small amount of glue is needed (I usually apply it to the pins.)

cleaning up. Once the joint is together, the end grain of the pins and tails will either stick up above the face of the boards, or be somew hat recessed. If it's recessed, you can use a plane to shave the face of the boards down, eventually getting to the end grain of the pins and tails, making them smooth. Fig. 11.

If the end grain is above the surface of the boards, it can be leveled with a file, lb protect the surface of the boards, place some heavy paper (from a grocery bag) in the path of the file, Fig. 12.

That's it, a perfect dovetail!

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