How To Choose The Right Joint For The Job

Very little can be accomplished in woodworking without using joints – either to bring pieces together or to make a rigid structure. I understand Bob has been in the industry for a little over a year and hasn’t worked with wood since junior high shop class. Biscuit joints are great for joining the edge of one board to the face of another. Shrinkage during cure is slight (probably under 1%) so that machined accuracy in mating joint surfaces is not necessary but still desirable, so as to produce a maximum quality bond. This is an interlocking joint where an angled male part fits into a similarly shaped female pocket. This is a common joint used to make wider boards and panels, such as table tops. With a 1″ thick wood chisel, now split the wood on this line until the piece is removed.

This joint would be weak in hardwood because the sheer plane is parallel to the wood fibers (so called short-grain). Joints may be as simple as one end of a piece of wood placed on another, or they may be as elaborate as several interlocking slots. This joint uses two dovetails on one side, one on the other: Cut into this narrow a board the small amount of material on the outer edges of the joint is weak in the piece shown on the left. Some epoxy adhesives require much less clamping pressure to produce acceptable joint strength. Even if the joint is very small, its structural and performance integrity rests on a perfect fit.

Glue is highly effective for joining timber when both surfaces of the joint are edge grain. Bernard l writes: Making these joints is truly considered as the toughest job so far i have concerned. Wood glues work by attaching to cellulose on the wood and the smoother (tighter) the joint, the less adhesive is needed to bond the surfaces. Other variations of the end lap joint include the cross lap joint, the edge cross lap joint and the middle T lap joint. Mi­ter joints may also be fastened with nails, screws, dowels, or other mechanical fasteners. To cut the slot, you push the handle in which extends the slot cutter into the wood.

The basic idea behind a mortise and tenon joint is that one piece of stock is inserted into the other, and then held in place with a fastener. First a sharp fine-tooth saw is used to cut along the two sides of the dado or groove, then a chisel is used to remove the waste wood inside the groove. Also, dovetail joints can be made manually, by drawing the shape and size of each dovetail onto the wood, and then cutting them with a back saw. The fibers of the wood tear and create hairlike fuzz on the surface of the wood.

So make sure you use a wood filler that can take stain, and be sure to wipe off all the glue that oozes out of a joint when you assemble it. A small amount of wood fibre was still adhered to the tenon, biscuit or dowel, but for the most part the joint failed at the glue line. Although more time-consuming to make, they have a major advantage over box joints as the shape of the tails and pins mean that the joint cannot be pulled apart.the wood joint

F. Immediately after clamping or nailing a member, the mechanic must examine the entire joint to assure uniform part contact and adhesive squeeze-out. This is a broad category of joints, so while there are many examples of corner joints out there, the definition is a joint that connects two pieces at their ends, thus forming a corner. When you make a joint such as a mortise and tenon you are not only making a mechanical joint you are also greatly increasing the glue surface area. To dress up a butt joint you can either countersink or plug your nail/screw holes.

End grain to end grain joints: in basic end-grain jointing, the squared ends of two members are butted together, end grain against end grain, to produce a longer length from two shorter pieces. The two or more pieces of timber in a butt joint adhere by crystallisation of the glue and atmospheric pressure. This indicates that glue surface area and glue penetration into the surrounding solid wood fibres is a key to joint strength. Knock-down (KD) joints are commonly used in flat-pack furniture, which is assembled by the customer at home. While it’s not a cure-all, wiping the wood with a solvent first goes a long way.