Woodworking Carcase Joints

Shadow smooths transition from frame to panel.

Shadow at joint line disguises uneven wood movement between assemblies.

Chamfer back / of face frame and case side before assembly to create V-groove.

Extend decorative spline past edge of assembly.

Chamfer top and breadboard end before assembly to create V-groove,

Breadboard Joint

A variation on the cogging technique: Here, Joel Evett and Roberta Boylen of Belmont, Massachusetts, juxtapose curved rings with straight-sided legs at the leg-to-rail joints on their "Fish Table."

PHOTO 8Y C€AN POWtU

Structures Bolts Joints

The three ebony details on this shelf unit by David Orth of Oak Park, Illinois, are actually caps that conceal bolts holding the two vertical structures together.

Photo tn AL caw sanding technique gives me greater control over the surface and saves time, since it's easier to sand individual parts than to deal with large assemblies.

You can also use cogging where two pieces of wood overlap. In the stepstool shown in the photo on page 52, the leg-to-leg lap joints are offset, offer- iry ing the same advantages as the face frame: visual interest, camouflage for wood movement, and A greater production efficiency. The offset is created J by using legs of different thickness and by ^

notching the leg members equally into one another, creating a mechanically strong joint.

The cogging technique also works well in a wide variety of corner joints. (See drawing.) I find chamfering or rounding over the protruding edges on coggcd joints accomplishes several goals. These "softened'' edges resist splintering, and they prevent a film finish like lacquer from peeling as it's prone to on sharp corners. Also, an angled or rounded edge is more inviting to die touch, and it looks good.

In an unusual variation of a coggcd joint, offset surfaces can be shaped to contrast sharply with one another, as shown in the tabic at right. Here, a ring detail where the curved rail joins the straight-sided leg adds interest to the joint and also melds the rounded, more organic form of the apron member with the more rectilinear lines of the legs, unifying the overall design of the piece.

The three ebony details on this shelf unit by David Orth of Oak Park, Illinois, are actually caps that conceal bolts holding the two vertical structures together.

Photo tn AL caw here one member passes through another, protruding beyond the surface. Like cogging, this technique adds flair and ensures that a picce looks good despite the movement of its individual parts.

I commonly use the protruding technique when I make a through mortisc-and-tcnon joint. I'm particularly fond of this joint because it's beautiful, fun to make, and it's one of the strongest joints you can devise when you need to join two pieces of wood. (For more on through mortise-and-tenon joints, see AW*18, and AW *29, page 49.)

But as with many joints, the beauty of a through tenon can be diminished if you don't ^ allow for the effects of wood movement. I learned this the hard way when I cut a through mortise and tenon on a stool I had designed for outdoor use, where wood movement is greatest. To complete the joint, I carefully pared the tenon perfectly flush to the outside of the plank it passed through. While the joint looked great at first, during high humidity the plank expanded in thickness and—because wood expands only marginally along

Devising Protruding Joints

The second design technique, using protruding elements, is similar to the first in that it involves non-flush members, but

Brad Schwartz of Deer Isle, Maine, creates a unified look in this matching desk and chair by using keys to secure his through tenons.

PHOTO BY DAWO KicmnsTF«

Brad Schwartz

Brad Schwartz of Deer Isle, Maine, creates a unified look in this matching desk and chair by using keys to secure his through tenons.

PHOTO BY DAWO KicmnsTF«

A variation on the cogging technique: Here, Joel Evett and Roberta Boylen of Belmont, Massachusetts, juxtapose curved rings with straight-sided legs at the leg-to-rail joints on their "Fish Table."

PHOTO 8Y C€AN POWtU

the grain—the tenon stayed the same length. The result was that the tenon end was recessed into the side of the plank-not the I(K)k I wanted at all.

Then, as the weather became drier, the plank shrank and the tenon stuck out % in. or so from the plank. "Aha!" I said, as the late-night lightbulb went on in my head, "Next time I'll begin by letting the tenon end protrude." Now, whenever the design allows. I make a through mortise-and-tenon joint with a tenon that protrudes at least in. to '/$ in. from its mortise—whether the piece will live indoors or out. (See drawing, previous page.)

The design of a protruding tenon can exert a powerful and dramatic visual effect on a piece of furniture, and it also can provide a means for hiding fasteners, as seen in the top

"tenons"

thai secure the two shelf units to one another

A wedged through tenon (see drawing) has a useful and rather unique advantage when you're dealing with fluctuations in moisture content, which can cause joints to become loose as wood swells or shrinks. When a wedged joint starts to loosen, you can retighten it simply by driving the wedge further into its slot. (See drawing.) Plus, with both wedged and keyed joints you can disassemble a piece by tapping the wedge out of its mortise, or by removing the key, and sliding the structure apart.

In addition to extending a through tenon beyond its mortise, there arc several other ways you can use protrusions as design elements and solutions for wood movement. One simple strategy is to extend shelves or dividers bevond

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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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