A biscuit joiner or biscuit jointer (or sometimes plate joiner) is a

woodworking Woodworking is the skill of making items from wood, and includes cabinetry, furniture making, wood carving, joinery, carpentry, and woodturning. History Along with stone, clay and animal parts, wood was one of the first materials worked b ...

tool used to join two pieces of wood together. A biscuit joiner uses a small

circular saw blade A circular saw or a buzz saw, is a power-saw using a toothed or abrasive disc or blade to cut different materials using a rotary motion spinning around an arbor. A hole saw and ring saw also use a rotary motion but are different from a c ...

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 Beech (genus ''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to subtropical (accessory forest element) and temperate (as dominant element of Mesophyte, mesophytic forests) Eurasia and North America. There are 14 accepted ...

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.

History

The biscuit joining system was invented in 1956 in

Liestal Liestal (, Standard ), formerly spelled Liesthal, is the capital of Liestal District and the Cantons of Switzerland, canton of Basel-Landschaft in Switzerland, south of Basel. Liestal is an industrial town with a Cobbled street, cobbled-street ...

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

, by

Hermann Steiner Hermann Steiner (1913 - 14 November 2005) was a Swiss inventor and businessman. In 1944, Steiner opened his carpenters shop in Liestal, Switzerland. He invented a system in 1956 that he called the Lamello Joining System which is now known as the ...

. 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 the 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 biscuit joiners. Several other companies such as Porter Cable,

DeWalt The DeWalt Industrial Tool Company is an American worldwide manufacturer of power tools and hand tools for the construction, manufacturing and woodworking industries, as well as home craftspeople. DeWalt is a registered trademark of Black & Dec ...

and

Makita () is a Japanese manufacturer of power tools. Founded on March 21, 1915, it is based in Anjō, Japan and operates factories in Brazil, China, Japan, Mexico, Romania, the United Kingdom, Germany, United Arab Emirates, Thailand, Indonesia, Mala ...

also manufacture compatible biscuit joiners, including some models with interchangeable blades, enabling the user to cut both biscuit slots.

Production

Biscuits are predominantly used in joining sheet goods such as

plywood Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that have been stacked and glued together. It is an engineered wood from the family of manufactured boards, which include plywood, medium-density fibreboa ...

particle board Particle board, also known as particleboard or chipboard, is an engineered wood product, belonging to the wood-based panels, manufactured from wood chips and a synthetic, mostly formaldehyde-based resin or other suitable binder, which is presse ...

and

medium-density fibreboard Medium-density fibreboard (MDF) is an engineered wood product made by breaking down hardwood or softwood residuals into wood fibre, often in a defibrator, combining it with wax and a resin binder, and forming it into panels by applying high tem ...

. They are sometimes used with solid wood, replacing

mortise and tenon A mortise and tenon (occasionally mortice and tenon) is a Woodworking joints, joint that connects two pieces of wood or other material. Woodworking, Woodworkers around the world have used it for thousands of years to join pieces of wood, mainly ...

joints, as biscuit joints are easier to make and almost as strong. They are also used to align pieces 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. Biscuits are also used to align edges of workpieces, such as when forming a 90° angle between workpieces. The biscuit provides a quick means of getting a perfectly flush joint, while at the same time reinforcing the joint. Typically, the machine will have an adjustable fence, so it can be set on an angle for joining mitered pieces. Also, there are other types of specialty biscuits available, from metal connectors, used for removable panels, to hinges, making these portable machines even more flexible.

Usage

The workpieces are brought together and the user marks the location for the biscuits. Precise measurement is not required, as the biscuits are hidden when the pieces are assembled, so a quick pencil stroke that marks both pieces where they align is all that is required. The parts are separated and the machine is used to cut the slots in each piece. The machine has reference marks on the centerline of the blade for easy alignment to the marks on the materials being joined. The body of the machine with the blade is spring-loaded, and in the normal position the blade is retracted. The operator aligns the machine and uses firm pressure to push the body forward against the base plate to make the cut. The waste material is blown out of the slot on the right of the base plate. Because the slots are slightly longer than the biscuits, it is still possible to slide the panels sideways after the joint is assembled (before the glue sets). This fact makes the biscuit joiner easy to use, because it does not require extreme accuracy or jigs to achieve perfect joints. The depth of the cut can be altered by an adjustable stop. The smaller base can be rotated through 90°, and accessories are provided for altering the offset of the base to the blade (for use with thicker or thinner materials as required). Some models allow slots to be cut at angles other than 90° to the joining face, for example 45°, which greatly speeds up the assembly of things like cabinets.

Standard biscuit sizes

Six-depth settings of biscuit joiner (six-size biscuits with no blade change) include Nos. 00, 10, 20, D, S, S6

Sizes of Porter Cable biscuits

The sizes were taken verbatim from the Porter-Cable website.

Detail biscuit sizes

Detail biscuits are smaller than standard biscuits and are typically used to join smaller pieces of wood together, and offer less structural support.

Blades and depth

For most portable plate joiners, a nominal 4-inch or 100 mm diameter blade is used for the Nos. 0, 10, 20 biscuit cuts. The blade is set deeper for joining the larger biscuits. Most blades have 4, 6, or 8 teeth and fit a -inch or 22 mm arbor. The thickness of the blade is typically 0.156 to 0.160 inch or nominally 4 mm.

Notes and references

* Bruce Gray, "Testing Joints to the Breaking Point", ''Fine Woodworking magazine'', No.148, April 2001. * sources : https://web.archive.org/web/20130717202631/http://www.lamello.com/fileadmin/user_upload/mediacenter/0%20Katalog/Lamello_Catalogue_EN.pdf {{Woodworking Woodworking hand-held power tools Joinery