Loose Biscuit Problem

When biscuits fit too loosely to align pieces accurately, the cutter may be the problem. June 15, 2009

Does anyone know whether there are biscuits available that are not compressed to be loose in the slot? We are hoping to use biscuits to accurately align panels when they are installed on the job, and the usual biscuits fit too loosely to be of help.

Forum Responses
(Cabinetmaking Forum)
From contributor J:
I've never seen the kind of biscuits you're talking about. Have you considered a spline made from hardwood or masonite instead? That's what I do.

From contributor L:
It was hard to discern from your post if you did, or did not, want biscuits that are loose. Any biscuits I've used are snug fitting but still easily inserted by hand. Biscuits are designed to swell a bit with the glue. Lamello used to make both plastic and metal biscuits for display work that would be set up and knocked down repeatedly. I don't know if they still do.

From contributor P:
I've taken to using 3/16 slot cutters and splines for accurate alignment. 1/4" Baltic birch ply, run through the widebelt until it's dead-nuts-on, makes great spline material.

From contributor U:
Have your slot cutter sharpened down to fit the biscuits better.

From contributor C:
I have not had much of a problem with biscuits fitting loosely in the slot, probably because I have a Lamelo. I also use the Lamelo biscuits, and have no alignment issues. You may wish to consider investing in a quality biscuit joiner, which will solve this problem.

From contributor A:
Which brand of jointer and biscuits?

From contributor G:
Hafele Furniture/Cabinetry Catalog. Pg 443, part #267.91.020, part name K20 plastic straightening lamellae.

From contributor D:
Most likely your biscuit joiner has grown sloppy over the years and is making a slot that is too large.Cut a slot and measure it. It should be 4mm thick. Lamello biscuits have the tightest tolerance at 3.9 to 4.01mm and should fit snug every time.

Lamello does still make the plastic and metal biscuits for both permanent and knock down assembly.