Woodworking Butt Joints Detailed Explanation
Visit Woodworking Plans Website for more woodworking tools details.The simple butt joint contains no interlocking parts, relying instead on the glue bond for its strength. The solidity of that bond is determined by the grain orientation of the mating boards. Gluing long grain to long grain, as in panel, edge,and face-to-face joints, produces a solid connection, requiring no reinforcement. All other butt joints involve end grain; this porous surface provides a much less effective gluing surface than an equivalent area of long grain. Therefore, end grain joints must be reinforced.
Nails and screws can be used for reinforcement, but cabinetmakers try to avoid them for two principal reasons: Additional work is required to conceal the fasteners, and neither does as good a job joining end grain as some of the alternatives. Screws are considered superior for one application, however, and that is the task of fastening a tabletop to its supporting rails. The technique, which involves drilling angled boards.
Most other joinery needs are filled by dowels, compressed-wood wafers or "biscuitsl" or splines, which can also serve to align parts of a joint that do not require reinforcement. Each demands mastery of a specialized technique-but the procedures are simple and they allow the quick assembly of strong, attractive joints in which the mechanical parts can be hidden from view.
At least one butt-joining technique--the butterfly key joint--is not meant to be hidden; in fact it is used as much for decoration as for strength. In this joint a doubledovetail key--the butterfly--is cut from a contrasting wood and used to tie together two edge-joined boards. The butterfly demands patience, but a well-set key can be a striking feature of a tabletop.
At the other end of the form-to-function scale is the use of threaded rods to reinforce such workaday surfaces as butcher blocks, workbenches, and countertops. These are often built up of face-glued stock, and the rods serve to stabilize the heavy slab when room humidity changes.Visit Woodworking Plans TV for more woodworking skills....