Subscribe now and save up to 56%
Relatively speaking, dowels and biscuits are modern innovations in joinery that have come about with the invention of power tools and jigs. As mechanical means of joining two boards, they are adequate substitutes for more traditional joinery techniques.
The Basics: • The dowel: Cylindrical pieces of wood are used to join two workpieces. • The biscuit: A thin football-shaped disk is used to join two workpieces.
The dowelDowels are wooden cylinders that fit into holes that are drilled into both workpieces. When the parts are assembled, they form a strong joint. Basically, dowels are a substitute for a mortise-and-tenon joint.
Dowels range in diameter from 3/16 in. to 1 in. and can be purchased at any home center or lumberyard, or produced from scratch. As a rule, the diameter of the dowel should equal 1/3 the thickness of the material. The minimum length should be at least 1-1/2 times the diameter. The number of dowels needed is determined by the width of the board, divided by the thickness. Dowels must fit tightly in the hole, and should be slotted, along their length, to allow excess glue to escape.
For dowels to provide strength and give the joint a good appearance, the holes must be registered accurately. Any offset or misalignment of the holes will prevent the joint from coming together properly or might cause the assembled joint to split.
There are several jigs on the market that ensure accuracy. Each type operates differently, but they all use bushings of various diameters. These bushings are positioned along the length or thickness of a board, to guide a drill bit at 90° to the wood surface.
The dowel was around long before it was used strictly as a mechanical joint. However, its historical use has been to pin traditional joints such as mortise-and-tenon joints and specialty joints.
The biscuit The Swiss company Lamello can be credited for bringing the biscuit joint to the masses. The introduction of its portable plate joiner, more commonly known as a biscuit joiner, allowed this modern technique for joining two parts to be used by hobbyists and professionals alike.
A biscuit (or plate) is a thin, football-shaped disk that works much like a floating tenon. Matching slots are cut into two workpieces, with each slot accepting half of the biscuit. When glue is applied to the joining parts, the biscuit expands in the slots and creates a tight-fitting joint.
Biscuits come in different sizes and are now made of different materials including plastic and metal. Their use depends on the materials being joined and the application.
Get woodworking tips, expert advice and special offers in your inbox
Become a member today
Get instant access to all FineWoodworking.com content.
Subscribe to Fine Woodworking
Save up to 56%
How a chunk of red oak forced me to rethink the details of a cabinet
Grids and cutouts define a practical piece
When a tenon loosened and broke on a favorite stool in our house, I wasn’t sure how to fix it. I don’t have a lathe, and it looked difficult to…
Make your cabinets stand out with clean, attractive through-tenons
I often make boxes with miter joints reinforced by small splines, or keys. After glue-up, while trimming the keys, I sometimes got a little careless with my Japanese saw and…
Shopmade L-shaped tenons create a powerful joint
Become a member today and get instant access to all FineWoodworking.com content!
Plus tips, advice, and special offers from Fine Woodworking.
Our biweekly podcast allows editors, authors, and special guests to answer your woodworking questions and connect with the online woodworking community.
Enter now for your chance to win a Lee Valley block plane valued at $160.
© 2016 The Taunton Press, Inc. All rights reserved.
Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.