A biscuit joiner offers a quick and easy way to make a spline joint. You use the joiner to cut mating concave slots and then simply install the specially shaped biscuits across the joint. Depending on the application, the joint can be completed in only a few minutes. For me, the big selling point is that with just a little care, perfect alignment of the joint is just about automatic.
Now I’m not advocating that biscuit joinery take the place of all other types. It’s a matter of choosing the most efficient and appropriate joinery method for the task at hand. And in many instances using biscuit joinery is a “no-brainer” — if you’ll pardon the expression. It can earn its keep by making otherwise tricky or time-consuming tasks easy, fast, and virtually foolproof.
Keeping edge-to-edge glue joints in alignment can be a challenge. Of course, one such instance is during a panel glueup. Once glue is applied and the clamps are tightened, the boards tend to shift, and you can end up with an uneven surface. A biscuit installed every 8" to 10" along the joints can cure the problem, In this instance, I don’t even bother to glue the biscuits into the slots. This simplifies the glueup while still guaranteeing a flat surface.
A similar application is shown in this drawing — wrapping a plywood panel with a solid-wood border. Again, the goal is perfectly flush surfaces. And in this case, cleaning up an uneven joint can be pretty touchy. Biscuits can be the answer. A bonus is a good measure of strength added to the joint.
