Biscuit joiner

A biscuit joiner (or sometimes plate joiner) is a woodworking tool used to join two pieces of wood together. A biscuit joiner uses a small circular saw blade to cut a crescent-shaped hole (called the mouth) in the opposite edges of two pieces of wood or wood composite panels. An oval-shaped, highly dried and compressed wooden biscuit (beech or particle wood) is covered with glue, or glue is applied in the slot. The biscuit is immediately placed in the slot, and the two boards are clamped together. The wet glue expands the biscuit, further improving the bond.

The biscuit joining system was invented in 1956 in Liestal, Switzerland by Hermann Steiner. Steiner opened his carpenter's shop in 1944, and, in the middle of the 1950s, while looking for a simple means of joining the recently introduced chipboard, invented (almost by accident) the now world-famous Lamello joining system. In the succeeding years there followed further developments such as the circular saw and the first stationary biscuit (plate) joining machine in 1956 followed by the first portable biscuit joiner for Lamello grooves in 1968. In 1969 the family operation was incorporated by the name of Lamello AG. Lamello continues to manufacture very high-end biscuit joiners such as the Lamello Top 20.

Several other companies such as Porter Cable, Dewalt, and Makita also manufacture compatible biscuit joiners, including some models with interchangeable blades, enabling the user to cut both 4" and 2" biscuit slots.

Biscuits are predominantly used in joining sheet goods such as plywood, particle board and medium-density fibreboard. They are sometimes used with solid wood, replacing mortise and tenon joints as they are easier to make and almost as strong. They are also used to align pieces of wood when joined edge-to-edge in making wider panels. It is important to use the same face when cutting the slots, so the boards are perfectly flush.

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