Wide

whle making cut

Catting the straight side of the socket is straightforward routing across a board.

while the pin is cut on the router table. I made it from three pieces of Va-in. particlcboard. The two long sides of the 3-in. piece must be accurately parallel, so check for constant width with a caliper, as you did for the square. Glue the edge of the 3-in. piece to the 8-in. piece, then immediately glue in the handle while it can still be used to ensure that the two pieces join at exactly 90°. Finally, drill a '/«-in. hole near either end, and insert a '/4-in. dowel as a stop.

The taper jig is used with both the T-square and the pin jig to make the taper on the pins match the taper on the sockets perfectly. I made mine out of 3/4-in. particlcboard. You can cut the taper on your tablesaw with a taper-cutting jig, or you can lay it out and carefully plane it by hand. Make the jig about l'/i in. wide and a couple of inches longer than the pin jig. I use a taper of l/tt in. per foot.

Two 1 -in. x /«-in. x '/«-in. hardboard stops on the ends of the jig key it to the pin jig for cutting the pins, as shown in Fig. 3, and less importantly, to the T-square, as shown in Fig. 2. Use the base of the pin jig as a spacer when vou glue the stops to the taper jig. If that makes it too tight for the T-square, shave the ends of the T- square head. Make sure there are no beads or smears of glue on the edges of the taper jig.

FIG. 3: CUTTING THE PINS

For scoring, feed stock with rotation of bit.

FIG. 3: CUTTING THE PINS

For scoring, feed stock with rotation of bit.

Score both sides and shape top side of pin with stock against fence.

Screw allows micro adjustment of fence.

ORIENTATION ^

Score both sides and shape top side of pin with stock against fence.

Screw allows micro adjustment of fence.

Shape tapered side of pin with taper jig between fence and pin jig.

Drill and Up for #10-24 screw.

Shape tapered side of pin with taper jig between fence and pin jig.

Drill and Up for #10-24 screw.

Bottom surface of stock gets // tapered side of pin.

Fence pivots here.

ORIENTATION ^

Fence pivots here.

- —vMMiie dovetail bit as used for socket Scoring prevents tear-out.

end of taper jig makes end of pin.

Front edge of stock gets narrow end of pin.

The micro-adjustment screw shown in Fig. 3 moves the fence over in very fine increments (handy for a lot of operations). To make it. I simply drilled and tapped a 1-in. x 5-in. piece of Vi-in. aluminum at one end for a #10-24 screw. If you round over the end of the screw with a file, it won't scratch or gouge the fence. I screwed a wing nut on tight to act as a handle for adjustments. If the screw tends to turn on its own when the router is running, add a lock nut. At 24 threads per inch, a quarter turn moves the screw about 0.010 in. Since the bit is half-way between the pivoting end of the fence and the moving end. a quarter turn of the screw moves the fence onlv .005 in closer to the bit.

Cutting the Joint

With the jigs made, you're ready to cut joints. I use a '/2-in. dovetail bit with a 14° angle. The 1 in 4 pitch of 14° simplifies working out the dimensions of the joint. You can use a different bit, but study the relationships between dimensions shown in Fig. 4 to help with the other changes you'll need to make. (With the Vj-in. x 14° bit, you won't have to change anything.) With the taper of Vie in. per foot of my taper jig. I can use the same jigs for Va-in. boards, forming a joint up to 24 in. long. I make the joints 3/i* in. deep.

To rout the socket, first mark the position of the top

Scoring 7m in. deep before the full depth cut prevents tear-out
The micro-adjustment screw provides fine adjustment of the router fence.
To cut the tapered side of the pin piece, place the taper jig between the router-table fence and the pin jig.

edge of the pin board, as shown in Fig. 2. For Va-in. stock, the centerline for the router should be Vi» in. below this point. Lay out the centerline on the stock, and if the dovetail is to be through (not stopped) square the centerline around the front edge, so you'll still have a mark after the first cut. Use the spacer to position and clamp the square half the width of the router base from the centerline. If you want to stop the socket for a blind dovetail, mark a stop line on the guide piece of the square. With the router base against the square, rout the straight portion of the socket.

With the straight side of the socket cut, put the taper jig between the square and the front edge of the board. Be sure that it causes the square to angle in

FIG. 4: JOINT DIMENSIONS

FIG. 4: JOINT DIMENSIONS

Suggested joint dimensions

Suggested joint dimensions

the correct direction; normally the taper will be on the bottom edge of the socket. Use the spacer to position the square from the centerline at the front edge, and clamp the square in place. Now rout the tapered (bottom) edge of the socket.

To cut the pins, mount the same dovetail bit in your router table, and adjust its height using the socket as a guide. Cutting slightly shallower is better than slightly deeper, so I use a .005-in. feeler gauge to position the bit slightly lower than the depth of the socket.

To prevent tear-out when routing the pins, I begin by scoring the stock. I do it by exposing the dovetail bit about l/\2 in. beyond the fence and taking a climb-cutting pass on both sides. (Climb cutting is when you feed the stock in the same direction as the cutter rotation. It is not normally done, because the cutter can grab the stock away from you. But just scoring the surface fibers to a depth of in. is quite safe.) Clamp the boards to the pin jig to keep them vertical. All the rest of the cuts can now be made against the rotation of the bit without tear-out problems.

Naturally the pins have to match the sockets, so they need a top (straight) side, a bottom (tapered) side, a front (narrow) end and a back (wide) end. Mark the sides of the pin boards that are to be tapered (usually the bottom sides) with an orientation mark as shown in Fig. 3 with the pointed end of the mark at the narrow end of the pin (usually the front edge of the stock). Be careful, it is easy to cut the pins incorrectly.

Now adjust the fence to expose the bit t/m in., as shown in Fig. 4. Rout the straight side of the pin with the top face of the board against the router-table fence and the orientation mark against the pin jig.

Cutting the tapered side of the pins is last. For this, the taper jig goes between the router-table fence and the pin jig and moves with the pin jig during the cut, as shown in Fig. 3. The hardboard stops key the two together.

To cut the tapered side of the pin. clamp the top face of the pin board against the pin jig with one edge against the '/j-in. dowel. Now with the taper jig against the fence and the pin jig nestled between the stops, the dovetail bit can cut the tapered edge of the pin on the outside of this sandwich.

Notice that both sides of the pin are cut with the top side of the board toward the fence. A board that is not uniformly thick will still receive an accurately cut pin.

For a perfect fit, we need to creep up on the proper width of the pin a shaving at a time. First cut the tapered side of the pin so the pin is clearly too wide to fit the socket. Here is where the last jig, the micro-adjustment screw, comes in. First test the fit. Each inch that the pin won't slide home corresponds to about .005 in. in the width of the pin. Use the screw to adjust the fence, but creep up on a perfect fit by trial and error. At least until you get a feel for it. don't move the fence over more than a quarter turn of the screw without testing the fit in the socket.

There is some leeway in the fit. You can use a mallet to tap the joint together about another inch, although when glue is added you will probably only gain in. If the pin is just slightly undersize, putting glue on both sides of the entire joint will tighten it up. Also, you can hedge your bets by using an extra-wide board and trimming either the front or rear as necessary after the joint is completed. However, if you use the micro-adjustment screw judicially other measures will not be needed.

When there are a lot of sliding dovetails to cut, it would be nice if all of the sockets were cxactlv the w same. With wood, they never will be. When doing blind (stopped) dovetails I create a stop for positioning the T-square by putting a small brad on the center-line for the router and cxactlv XU in. from the front edge. The small hole will be covered by the pin board. The brad is removed for any routing but ensures that the taper cut will be positioned in the same way as the straight cut. This system is very precise by woodworking standards, plus or minus a few thousandths, but it won't eliminate trial fitting of the pins.

To make cutting the taper on a lot of pin boards easier, I first separate the right-hand joints from the left-hand joints, and treat them as two batches. I work on just one pin in one of the batches until it almost fits in the largest socket. I then cut all the tapers in the batch with that setup and check their fit. For the next trial fitting. I turn my adjustment screw an eighth of a turn and take another shaving off all of the tapers. Some pins will fit, but others will still be too large. Another eighth of a turn on the screw reduces the oversize pins again. A third reduction in size may be needed for a few lapel's. I then start over for the other batch. Right-hand and left-hand joints can't be done in the same batch.

One final word of caution: Try to arrange your work so that the joints will be assembled very soon after they are cut. A change in humidity could present a real headache. Satisfaction comes from making a rugged joint that industry is pretty unlikely to replicate. A

Hi Curtis Johnson is a hiophvsicist in the Department of Biochemistry! Biophysics at Oregon Slate Uniwr-sity. He is also a part-time professional woodworker and contributing editor for AW.

Discover the Pleasures of Doing It by Hand m e s willing to rip everything into narrow strips and re-glue. (You can reduce boards to uniform thickness with a planer alone, but it won't make them flat.) Flattening, thickncssing, edge joining and gluing enough strips for a 36-in. tabletop is no picnic. And there are times when you just don't want to cut a nice, wide board into strips.

A hand plane allows you to flatten any board, regardless of the board's width, length or thickness. Flattening piles of boards with a hand plane can be strenuous and tedious work. (It was deemed an ideal character-building task for generations of apprentices.) But if you don't have access to a wide jointer, you have no choice. Even if you do, it's useful to know how to flatten boards by hand. If you understand the hand technique, you'll use your machines more skillfully. And when you get a special, wide board, you'll be able to work with it intact.

Tools

You don't have to spend a lot of money for machine tools to flatten and thickness boards. All you need arc a sharp hand plane and a workbench, a pair of winding sticks—two straight sticks that gauge the twist of a board—and a marking gauge.

I do all my hand planing with an old Stanley 07 jointer plane. Its 22-in. long sole bridges high spots on a board, instead of riding up and down on them as a shorter plane would. It's heavy, so I don't have to bear down to get the job done. The only drawback is its narrow throat. Because I use this one plane for everything, I've set the throat for finer work, so when I use it for rough planing, the thicker shavings have a tendency to clog the throat. This just means I have to stop and clean out the shavings a little more often. If you plan to do a lot of rough planing, you could do what the old-timers did, and use a scrub plane with a wide throat and a blade that's slightly rounded across its width. A scrub plane is capable of removing a lot of

learn the techniques of planing by hand, and you'll be able to flatten any board, regardless of size.

rou don't have to work with wood very long to discover that few of the boards you buy are flat. It doesn't matter whether they come surfaced on two sides (S2S) from the local building supply or roughsawn from a lumber mill. Nor does it take long to find out how frustrating it is to work with boards cupped across their width or bowed or twisted along their length. Joints are difficult to lay out and cut, and assembly is a struggle, generally won only by brute force and well-chosen words.

So if you're going to work wood successfully and continue to enjoy it, you'll need to learn how to make boards flat. A 4-in. or 6-in. jointer will do the job if you're

learn the techniques of planing by hand, and you'll be able to flatten any board, regardless of size.

Sight along plane of board so winding sticks align at one end (A), then look across to other end (B) to gauge the amount of twist Plane until sticks align at both ends.

Planing against a simple stop across the end of the bench keeps the board from sliding.

Planing against a simple stop across the end of the bench keeps the board from sliding.

Sight across the top edges of a pair of winding sticks to see if a board is twisted along its length.

wood quickly. Whatever plane you use, don't worry about the size of the plane you use. Any bench plane (smooth, jack, fore or jointer) will do. It's more important that you feel comfortable with the plane, and keep it sharp.

A workbench fitted with a tail vise and bench dogs is ideal for face planing all but the longest boards. Unfortunately, I don't have one in my current shop, so I've rigged up an adjustable stop on the end of my simple, slab benchtop, as shown in the photo on page 32. I've found that planing into this stop works for most boards, even when planing diagonally across them, A bench dog or two in the holes along the back of the bench helps to hold boards that would otherwise slip around.

It's important that the top of your workbench be flat. A llat benchtop serves as a gauge for determining a board's deformities. It's difficult to plane a board flat, particularly a thin one, when it's supported by an undulating surface. Planing your wooden benchtop is an ideal way to practice flattening a surface—it's thick enough so you can keep at it until you get it right.

Winding sticks help you gauge how much a board is twisted along its length. (A twisted board is said to be "in winding" or "wound," hence winding sticks.) They're simply two long, narrow pieces of wood of exactly the same width, as shown in the photo and Fig. 1. They're easier to use if the top edges are two contrasting colors. A handsome mahogany pair I've seen had inlays of ebony on the top edge of one stick and holly on the other. At the other end of the spectrum is the simple pair I recently made. I was in a hurry, so I

FIG. 3: FLATTENING THE CONVEX FACE

STEP 2: Extend the flat with alternating diagonal strokes.

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Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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