Finger Joint Boxes

Toy Chest Joinery

Interlocking Joints

Just as most craftsmen consider mortises and tenons the best choice for connecting rails to stiles, legs to aprons, and for other frame joinery, they favor interlocking joints for assembling the sides of boxes, drawers, and chests — what is commonly referred to as box joinety. There is an important difference between these two types of joinery Mortises and tenons join boards whose wood grain is oriented to shrink and swell in different directions. Interlocking joints, on the other hand, connect boards that move in unison.

This unity of movement allows you to cut intricate mating surfaces when making interlocking joints. Frame joinery is often very plain; if it were too elaborate, gaps would open up between the adjoining members as they expanded and contracted. This, in turn, would weaken the structure. But box joinery, such as dovetails and finger joints, can be as fancy as you want to make it. Consequently, many interlocking joints are both decorative and practical.

Increasing Gluing Surface

Interlocking joints include various types of dovetail joints, finger joints, and lock joints, all of which require multiple cuts. (See Figure 6-1.) The common purpose of these joints is to increase the gluing surface in a corner joint. The mating surfaces of simple corner joints (butt joints, miter joints, and rabbet joints) are relatively small. Often, there are no long-grain-to-long-grain surfaces, just end-grain-to-long-grain and end-grain-to-end-grain. These circumstances combine to make a weak joint. The multiple cuts in an interlocking joint multiply the surface area and often provide a healthy measure of long-grain-to-long-grain gluing surface.

Despite these multiple cuts, interlocking joints are not difficult to make. It's the number of cuts that cause an interlocking joint to look intricate, not the complexity of the cuts. Most joints require just one or two simple cuts that are repeated over and over again. As long as your layout and setup are accurate, the actual cutting will prove very easy.

Interlocking Wood JointsWoodworking Archive BizDifferent Types Wood Joints

6-1 Of the many different types of interlocking joints, here are four of the most common: A finger joint (1), also referred to as a "box joint," is used to join the corners of boxes. A through dovetail joint (2) joins boxes, chests, and the rear corners of drawers. A half-blind dovetail (3), which can only be seen from one direction, is often used to join the front corners of drawers. A lock joint (4), also called a tongue-and-dado joint, is another joint that can only be seen from one side. It's often used to join the corners of drawers, especially small ones.

finger joints

Finger joints are interlocking notches cut into the ends of adjoining boards. Usually, the notches are spaced evenly and they are all the same width. You can cut all the notches in both of the adjoining parts with a single setup, using a miter gauge and the "Finger-Joint Jig" shown on page 84.

The jig is designed to work on either a table saw with a dado cutter accessory, or a router table with a straight bit. You'll find that it's easier to make all sizes of finger joints on a table saw. It's simple enough to make small finger joints in thin stock on a router table, but the procedure becomes progressively more time consuming as the fingers grow wider and the stock gets thicker. Remember, routers are designed to remove only small amounts of stock at one time.

When making finger joints, the setup is critical. The width of the stop on the jig, the width of the cutter, and the distance between them must all be precisely equal. Plan to make several test joints to fine-tune the setup before you cut good stock. (See Figures 6-2 through 6-6.)

Finger Joint Jig Plans
joints, make sure the width of the stop and the width of the cutter are precisely the same. Slide the face of the "Finger-Joint Jig" on page 84 to one side or the other until the distance between the stop and the cutter is equal to the other two dimensions.

Here are several additional tips:

■ The width of the adjoining boards should be a multiple of the fingerwidth. For example, if the fingers are xh inch wide, the adjoining parts might be 5 inches, 5V2 inches, or 6 inches wide, but not 5V* inches or 57« inches. If you can't divide the finger width into the board width evenly, you'll end up with partial fingers on one side of each board.

■ The fingers should be at least as long as the width of the adjoining board. To be certain that they are long enough, cut them about V32 inch longer than needed so they protrude slightly when the joint is assembled. Later, you can sand them flush with the wood surface.

■ Scribe the base of the fingers with a marking gauge — this will help prevent the bit or cutter from tearing the wood grain.

■ As you cut each board, back it up with a scrap. This too will prevent tear-out.

Back Gauge Fingers

6-3 Place the first adjoining board end down against the face of the jig and slide it to one side until the edge butts against the stop. Clamp the board to the jig to prevent it from moving. Turn the saw on and slide the board foiward, cutting the first notch. Note: To prevent tear-out, always back up the board with a scrap.

6-3 Place the first adjoining board end down against the face of the jig and slide it to one side until the edge butts against the stop. Clamp the board to the jig to prevent it from moving. Turn the saw on and slide the board foiward, cutting the first notch. Note: To prevent tear-out, always back up the board with a scrap.

6-4 Loosen the clamp and move the board sideways until the notch you just cut fits over the stop. (It should fit snug, with no perceptible slop.) Tighten the clamp and cut another notch. Repeat until you have cut all the notches in the first adjoining board.

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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Responses

  • biniam
    How to cut interlocking notches into a wooden box side?
    4 years ago
  • tricia
    How to make wooden box with interlocking joints?
    2 years ago
  • helen milne
    How to cut interlocking wood corners?
    2 years ago
  • Lobelia
    How to make a wooden tool box joints?
    1 year ago
  • nairn
    What h is a joint which can be used for the corners of boxes?
    1 year ago
  • ryan marshall
    How to make finger wooden joints?
    10 months ago

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