Because biscuit joints are easy to mark out and quick to cut, using one almost seems like cheating. The safest way to cut biscuit slots is with a biscuit joiner. The oversized slot lets the biscuit move slightly, enabling you to tweak parts into perfect alignment.
“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.
Hey there! So I have always just glued up my table tops with no joinery except glue. I’ve recently had some problems with cupping with my tops.
Properly-cut biscuit joints are strong and accurate, particularly when cutting slots with a woodworking tool called a biscuit joiner. When glued into slots precisely cut by the biscuit cutter, and the moisture from the glue causes the biscuit to swell and tighten the joint. As a general rule, try to use the largest size biscuit possible, as this will provide the greatest amount of strength to the joint.
biscuit joiner grain direction Related Question:
Why does the grain of a biscuit run diagonally?
Biscuits are made from compressed beech wood. The grain runs diagonally across the biscuit. The biscuit is weakest along this grain line. When you install two biscuits in a joint, put them in with the grains running in opposite directions.