How should I join everything (it's dry fitted right now)? Is glue enough? Biscuits? How do I get clamping pressure on the "lid"? It isn't shown but I also cut a panel mitered on all 4 sides which sits right on top making it kind of look like one block of wood. Also, is there anything I can do to the seams to make them seamless? It's seriously within 1/32" or maybe even less but you can still see a slight line. I plan on staining and sealing with poly.... will that do it or is there another trick?
Nice work!
Joining mitered corners is a matter of some debate. If you just apply glue and try to throw some regular bar clamps on the piece, the miters will slip right past each other and the whole thing will collapse! There are a couple of alternatives that depend on what tools you have available. I'll focus just on joining the sides of the box together. Once you've done that, the rest is easy. Here are some options:
1) If you've got tight-fitting miters, and it sounds like you do, the cheapest alternative is to use wood glue and packing tape. The basic idea here is that you dry-fit the joints, then tape them together on the outside with clear packing tape (or any other tape that's strong and won't leave nasty residue behind when removed). The tape acts like a hinge to prevent the corners from falling apart. Tape 3 of the 4 corners. Then you sort of "unroll" the piece, spread glue on all of the joints, fold it back up, and tape across the fourth corner.
I've done this with small, solid wood boxes and found it to work well for that purpose. The tape doesn't provide a whole lot of clamping pressure, so it may or may not be possible to pull a gap together. And you need to be pretty careful to make sure you don't pull the whole thing out of square once you apply the glue.
2) You can use special corner clamps to hold the project together. I own several of the cheaper versions:
http://www.woodcraft.com/family.aspx?FamilyID=4250http://www.woodcraft.com/family.aspx?FamilyID=4384Which really aren't worth the money. They're not necessarily an exact 90-degree angle, don't provide much clamping force, and have never given me great results. I've used the heavier duty version of this Bessy corner clamp:
http://www.woodcraft.com/family.aspx?FamilyID=4249And it works pretty well, but the price is pretty absurd. I also own a bunch of these 3D squares (which I bought directly from the manufacturer at a woodworking show for about half Woodcraft's price):
http://www.woodcraft.com/family.aspx?FamilyID=4484These work very well. The configuration that the Woodcraft picture shows is an especially good one: you clamp a couple of pieces of scrap wood to one square, then insert the piece you want to glue, the put another square on the inside of those pieces and pull the whole thing together with clamps. It's
great for flat pieces, but probably not so useful in your situation.
I've heard good things about the various forms of miter spring clamps:
http://www.woodcraft.com/family.aspx?FamilyID=5151http://www.woodcraft.com/family.aspx?FamilyID=3860But haven't tried them. They make small holes in the wood, which I've never been a fan of.
3) Mechanical reinforcement of the joint isn't a bad idea. I've used pocket screws and biscuits in this situation. I've always found that getting biscuits properly aligned on 45-degree miter joints is a bit of a hit or miss proposition. Just when you think everything is right, something will move a little bit and your biscuit slot will end up 1/32" or more from where it really should be. Pocket screws are a better bet, in my experience. You'll make the holes on the inside of the piece, so they won't be seen. What I like to do is make a perfect 90-degree corner to use as a jig. I'll drill the pocket screw holes in one of the sides, apply glue to the wood, push the two sides against the jig, check the fit, and then screw everything together. In theory, pocket screws may also be able to pull a corner together if the fit isn't quite tight.
4) The final option, which can be a bit tricky, is to use bar clamps. I know: it can't be done. The trick is to take scrap wood and use it to support the box while you're using the clamps. I'd cut a piece for each end and a couple of pieces to run along the length. You can use any old wood, though it helps if it's straight. The idea is to be able to pull the corners tight using the bar clamps, but have the scrap pieces resting inside the box prevent it from collapsing. If that makes any sense...
Finally, I'll suggest that it's probably more important to get the miter joints to close up than to have each corner be absolutely, square. If your gaps are 1/32" or less, you're close enough. It's not going to matter if you have to squeeze the joint from a perfect 90-degrees down to 89.75-degrees. It will be very noticeable if there's a gap at any corner, however.
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Topic: 45 mitre failures (Read 6734 times)
