Proper gluing techiniques

[Dan Mages]

I have a quick question for all of us newbies. What is the best method to glue a few pieces of wood together and make sure that the end result is perfectly flat?

Thanks!

Dan

[Jim Becker]

Use cauls to keep the surfaces flat while things are clamped up...or buy a very expensive panel clamp system. Of course, sometimes the wood still has a mind of its own... ;)

Cauls are merely some material, typically some boards made from strong solid stock that have a very slight crown in the middle. The crown makes it so that you can get more even pressure in the middle of the panel due to compression when the ends of the cauls are clamped together as a "press".

[Lee Schierer]

#1. Make sure all the edges are perpendicular to the face before you start.

#2. Work on a flat surface and check for flatness before the glue dries.

#3. Do a dry run. If it won't come out flat or square dry, it won't with glue on it. The dry run will also point out any special precautions or clamp setups you need for the final glue up.

#4. If the pieces aren't perfectly flat as you are working, bend each piece slightly during the clamp up to make the faces align.

#5. Evenly space the clamps and alternate them from side to side, making sure the amount of pressure each is applying is uniform.

#6. Apply any stain that is likely to be hard to get to or suffer from glue squeeze out before you apply the glue.

[Keith Christopher]

I would only add here to the fine advice is, if you can use a biscut jointer properly it can help in the alignment on glue up.

1) Always use cauls to keep the boards from popping up on you.
2) Don't use so much pressure that you squeeze most of the glue out by over clamping. (too tight clamps make bowing a problem as well)

If you're forcing a board gap closed by clamping the heck out of it, you're over clamping boards that don't have flat, clean, straight (square) glue edges.