On Menu 1: Biscuits

Biscuits were on today's menu at the house.  Not the kind the Pillsbury Dough Boy giggles over!  Not the kind Grandma used to make from scratch!  These biscuits join two pieces of wood.

In this case the wood is oak for the stairway treads, each tread consisting of two boards joined by — you guessed it! — biscuits.  This method of joining wood was invented in 1956 by a Swiss carpenter.  Porter Cable and other manufacturers make biscuit joiners for the American market.  The equipment (termed a biscuit joiner or a biscuit jointer, depending on the maker) can be either stationary or portable.  Both woodworking tools do essentially the same thing.  A small (4-inch) tungsten carbide tipped circular saw blade is used to cut a crescent-shaped hole (the mouth) in opposite edges of two boards so that the holes are exactly aligned.  Glue is applied to the edges with the holes.  An oval-shaped wooden biscuit, usually made from dried and compressed beech, is inserted into the mouth.  Then the boards are put together and clamped.  The wet glue causes the biscuit to expand and creates a bond which can be stronger than the wood members themselves.

The tools — a portable biscuit joiner (or jointer)...

...the biscuits...

...and wood glue.

Dave was working on stair treads today, while Kyle was cutting wood for book shelving (see the second post for today).  The photos describe the process:

Dave applies wood glue to the surfaces to be joined.
Note the narrow hole, or mouth, in the board.

He uses a biscuit to spread the glue evenly along the surfaces...

...places a biscuit firmly into each mouth on one board...

...and then joins the two boards and taps them together.

All this is done as quickly as possible, because the glue sets up fast.  Two sets of boards are clamped together using two pipe clamps, excess glue is removed, and then a third pipe clamp is put in place.  After that the boards go off to the downstairs bedroom to dry.

Dave applies clamps at both ends...

...scrapes off excess wood glue...

...and then the clamped sets of boards are put aside to dry.

At this stage the boards are oversized for stair treads.  When the time comes they will be cut down for an exact fit.  However, thanks to biscuits and glue, these treads aren't likely to break when heavy furniture is moved upstairs!

For a look at what Kyle was doing today, keep reading! •••