gluing and clamping box joints

[softop41]

I had never made a box joint before today. It came out nicely on some scrap pieces using a slight adaptation of the jig from www.newwoodworker.com.
Then I decided to see how well it glued up. I got it done, albeit, rather awkardly. So, I figured with all the knowledge, wisdom, and experience of the members here that I should be able to find out how it can be done more expediently.
Any and all ideas/comments are welcome.
Thanks
Jerry

[gmack5]

The best way to glue up a box joint, IMHO, is to use "cauls" on each side of each corner to be glued up.

A "caul" is nothing more than a length of wood or other material used to distribute the pressure during the glue-up process. A length of 2 X 2 would work well for the type of job you have in front of you.

Just position a pair of "cauls" about 1" inboard from the corner on opposite sides and apply one or two clamps, depending on the length of the joint.

Since the pins on Box Joints normally stick out a bit beyond the mating surface and are then sanded down flush after the glue dries, using a caul will avoid attempting to put pressure directly on the pins in the joint.

I hope this is clear, if not, post your question and I'll attempt to answer it.

[Black wallnut]

I agree with George! Really shallow drawers you may even get by without cauls; just be sure to place the clamp(s) a little bit away from the joint.

[Tom Miller]

Be careful to maintain square corners when clamping inboard of the joint, as too much clamp pressure can bow the sides of the box inward. The resulting joint will be something less than 90 degrees, with a lot of glued surface area to keep it that way.

The amount of bowing will depend on several factors, including length and thickness of sides, clamp pressure, and distance of clamp from corner.

Regards,
Tom

[boblon]

Tom is right about that...DAMHIKT !!

BobL.

[LCHIEN]

Fine woodworking magazine last month's issue (May? or June?; another one came about 5 days ago)
has an entire article about glue-ups.

They had a paragraph on the right way to glue up box joints and dovetails... there's a certain way to apply the glue - IIRC you don't apply glue to any end grain.
(although if you are sanding off the protruding end grain as the previous posters suggested, I guess it doesn't really matter.

[tmaceroli]

I just finished gluing one up myself. I think it depends on the wood species a little bit. I used oak, so I didn't really have to worry about bowing the sides too much. Also, I clamped near (not on) the joint. A previous poster is correct. Since you want to make the pins about 1/32" longer than the width of the side to which it is joined and sand them down after the glue has dried, you have to clamp an inch or so away from the joint. I used an acid brush to get glue into all of the joints on all surfaces. I'm not sure about the comment not to glue any horizontal surfaces. When you've got that many surfaces to glue, and not that much time to get them all done, there was enough glue around to get on many other horizontal surfaces not even remotely connected to the joint.

One trick for the inside of the box is to put masking tape across the side, right under the cutouts for the pins on each side. Any glue squeezout goes on the masking tape. The inside of the box is much harder to sand, and therefore much harder to remove the glue squeezeout. The outside is easy, since you're going to sand the pins down, and the glue gets removed as an added bonus.

The idea of the cauls is a good one, except to make sure the cauls don't accidentally get glued to the side of the box, you really need to be careful. Like no accidental glue on your hands, etc. I opted for two clamps for every joint on each side, i.e. 8 clamps total. Once dried, I sanded the **** out of it to get the pins even with the box sides, and to ready the box for finishing.

Also, make sure the box is square as you're setting up the clamps, and make sure it stays square as you tighten down on the clamps for each side. Sounds like a lot, but it's not too tough. Sounds like you're pretty far along already.

Good luck!