When gluing boards together, woodworkers sometimes use biscuits, and sometimes they just put glue on the edges and clamp. Is there a rule on this subject?
Carol Reed: No rule here. Glues today are stronger than the wood so biscuits are not needed for strength. Because biscuits help align the edges, there is some value in using them with long edge joined boards. I rarely use them, and never use them on short boards. Your choice.
Lee Grindinger: No, there is no rule. Biscuits are used to help align the boards but they do not add significant strength to a joint. In some cases, the material used in the biscuit will react to moisture differently than the rest of the wood. When this happens the biscuits can telegraph through. For works intended to outlast the glue used, pieces built for generations, use a proper joint like a tongue and groove or a profile called “glue joint” that adds a mechanical strength to the joint. Wood moves, and most glues can’t keep up for centuries on end, so a mechanical joint will keep the piece serviceable when half the glue in the joint has failed.
Mark Hensley: I use biscuits if I’m gluing a bunch of boards together to help keep them aligned. If I have one or two boards, I just glue them.