Biscuits used to join pieces of wood are oval-shaped, thin, dried, and compressed bits of wood or wood shavings, often made with beech wood. A tool known as a biscuit joiner cuts a slot into each of the two pieces of wood to be joined, adds glue to the slots, inserts the biscuit into one and then the other to join the pieces together. The biscuit joiner aligns the slots precisely so that when the two pieces of wood are clamped together, the edges align perfectly, and the wood’s plane is maintained.
Years ago, back in the 1990s and early 2000s, a biscuit joiner became a very popular woodworking tool. Well, as much as I admire Norm Abram, a biscuit joiner may be one of the most useless power tools you can own. If you’re new to woodworking, or if you’re a maker, you may not even know what a biscuit joiner is.
“The slot for a #0 biscuit measures about 21⁄8” wide, so you can’t hide a biscuit joint in stock narrower than this. Even a well-tuned biscuit joiner can sometimes cut slots that result in a non-flush-fitting joint. Cutting the spline slots on your tablesaw requires a tall jig, but you can cut them easily and quickly with your biscuit joiner and the attached fence jig, see drawing below.
biscuit joiner drill attachment Related Question:
What can I use instead of a biscuit joiner?
Some tests suggest a dowel joint will provide stronger joinery than biscuits. Tests also indicate that dowel joints are not as strong as tenon joints or dovetail joints. They do make solid and accurate joints, though. A dowel joint will be a better method than nails or screws and are much less susceptible to breakage.
Can a router be used as a biscuit joiner?
If you want to make biscuit joints, you don’t have to buy a biscuit joiner. In most cases, a router equipped with a 5/32-in. slot bit can cut perfect slots to fit the biscuits. Mark the biscuit positions on both adjoining boards as you would with a biscuit joiner.
Are biscuit joiners worth it?
Biscuits joints serve best as a quick and easy way to keep glue-up parts in alignment, and that they add appreciable pull-apart to strength joints that would be otherwise too weak to stand on their own – like butt joints and miter joints.