Butt joint

A butt joint is a technique in which two pieces of wood are joined by simply placing their ends together without any special shaping.The name 'butt joint' comes from the way the wood is joint together. The butt joint is the simplest joint to make since it merely involves cutting the wood to the appropriate length and butting them together. It is also the weakest because unless some form of reinforcement is used (see below) it relies upon glue alone to hold it together. Because the orientation of the wood usually presents only one end to long grain gluing surface, the resulting joint is inherently weak.

The butt joint is a very simple joint to construct. Members are simply docked (cut off) at the right angle and have a required length. One member will be shorter than the finished size by the thickness of the adjacent member. For enclosed constructions, such as four-sided frames or boxes, the thickness of the two adjacent members must be taken into consideration. For example: when constructing a four sided box made from 19mm thick material that is to be of finished size 600mm x 600mm, two of the members will be docked at 600mm and two will be docked at 600mm - 19mm - 19mm = 562mm.

Reinforced butt joints may require additional steps which are detailed below.

In solid timber, docking of members for a butt joint is usually a crosscut, so a crosscut saw is best for this job. When working with sheetgoods, there is no distinction between crosscut and rip cut.

The joint members can be docked by any of the following methods:

To overcome their inherent weakness, butt joints are usually reinforced by one of the following methods:

This is the most common form of the butt joint in building construction. Members are brought together and a number of nails are driven in to hold them in place. The technique of skew-nailing is applied so that nails are not parallel to each other and so resist the pulling apart of the joint. This form of butt joint is rarely used in furniture making.

Use for:

The dowel reinforced butt joint or simply dowel joint has been a very common method of reinforcing butt joints in furniture for years. They are common in both frame and carcase construction. Dowel joints are popular in chairs, cabinets, panels and tabletops. They are also used to assist with alignment during glue up.

The technique consists of cutting the members to size and then drilling a series of holes in the joint surface of each member. Holes are often drilled with the assistance of a dowelling jig which aids in accurate hole placement — accuracy is paramount in this technique to ensure members line up perfectly in the completed joint. The holes are drilled such that there are corresponding holes in each member into which short dowels are inserted with some glue. The joint is brought together and clamped until the glue has dried.

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Wikipedia