Joints for enclosures

[nubbins]

Just some food for thought...

Making Strong Wood Joints

[CrisTUFR]

Another interesting link if you are interested in building your speakers lock-miter style.

I think that the lock-miter technique is probably optimal with plywood, since you want to hide the ply at all costs.

If you lock miter, where do you do it? I'm assuming you build the "frame" (top, sides, bottom) that way, but there must be a different way to affix the front and rear baffles.

Any woodworking pros in the house?

[markp]

Originally posted by CrisTUFR


Do you have a model name, number, or picture for us?

Thanks,
Chris

Try http://www.rockler.com/ecom7/product...erings_id=2142

[Philo]

If you lock miter, where do you do it? I'm assuming you build the "frame" (top, sides, bottom) that way, but there must be a different way to affix the front and rear baffles.

Using a miter joint on a speaker is "do-able" but takes quite a bit of practice, set up and an occasional third hand to get it assembled with glue. If you look at the joint you can see the "direction" of assembly. Looking at the picture on the Rockler page, the left piece of the joint would be on all four sides of your top and bottom and on the vertical edges of the front and rear baffles. This is important as it will allow you to assemble in steps. At the corners of your baffles you are going to get a mismatch. You need to make a compound 45 degree notch cut across the corner where the two diferent patterns meet without cutting off any of the visable (after assembly) wood. This cut begins at the back of the board and goes 3/4-7/8 of the way through the board and looks like a dogeared page crease of a book. Make a few test boards and you'll see what I mean. You have to be close and accurate with this cut as it will leave a pocket in the joint if you cut out to much. Assemble the vertical sides first, clamp them snugly with two strap clamps, then put on the top and bottom. Clamp the top and bottom with bar or pipe clamps, then fully tighten the strap clamps. If you don't do your clamping in steps of pressure you'll rack the sides out of square and not get the top and bottom on before the glue sets.
Here are some other hints for miter lock joints:
1) USE A ROUTER TABLE with a tall fence or optional horizontal mount!!! Your joints with come out much much cleaner and better fitting. Feather boards are also a plus.
2) Use 45 deg bevel bit to remove some of the material before you use the miter joint. Your miter bit will last much longer and you get cleaner joints.
3) Once you get the router table properly set up for each cut make a setup sample to use as a guide for the next time. This is a major time saver in the future.
4) Do a FULL dry assembly first before you apply glue so you can check your joints. Use plenty of glue in corners for speakers as this needs to be airtight.

[markp]

The Rockler router bit makes panels that assemble very easily. They almost hold each other together which is why they are so airtight too. Large glueing surfaces create a bond that won't let go ever.
Take a look at their bevel router bits too to make multi-sided boxes that sound and look great compared to a cubish thing.
As a side note, don't dado in your braces as it weakens the panels structure. Just butt glue them in or use two or three small biscuits.