Joining two panels when making speaker cabinets

bdp24 · « **on:** 23 Feb 2013, 01:24 pm »

At the cost of displaying my ignorance, I have to ask why I never see speaker boxes joined at any two walls with those walls cut at 45 degrees inward, so that the seam is just a thin line on the very edge? Everybody does a butt-joint instead, which leaves a seam 3/4" in on one wall. There must be a reason, but I haven't seen it mentioned.

S Clark · « **Reply #1 on:** 23 Feb 2013, 02:11 pm »

Butt joints are weaker but faster. Wood glues are so strong today that butt joints are strong enough to do the job... esp. when using mdf. Miter joints are hard to do well on most table saws.
Scott

jparkhur · « **Reply #2 on:** 23 Feb 2013, 02:12 pm »

Some people like butt joints better than 45s. I do both but to get all the panels perfect without a cnc machine I at times struggle. Sides first then drop in the top and bottoms. I have never been perfect and always had to do some light edge work. I like grain so if I do but joints I always to a bevel or round over which makes it appear as if they could be either. There is similar about of glue surface on both. Also most high end companies use a laminate to hide all joints anyways. Ill post and example of a butt that looks like 45

jparkhur · « **Reply #3 on:** 23 Feb 2013, 02:15 pm »

On my recent super v project I also used pocket screws to help with strength anywhere I could hide them

pecker · « **Reply #4 on:** 23 Feb 2013, 02:35 pm »

Quote from: bdp24 on 23 Feb 2013, 01:24 pm

There must be a reason, but I haven't seen it mentioned.

Most folks are not cabinetmakers, or even proficient woodworkers.
You have to be able to veneer your substrate first, or use plywood, and be able to make accurate cuts. Unless you're just going to try to veneer after the fact, in which case the joinery doesn't matter too much.

This pic almost looks like it's one wide board, but it's a mix of veneer and solid wood with both 45 degeree bevels and roundovers.

srb · « **Reply #5 on:** 23 Feb 2013, 02:38 pm »

A 45 degree lock miter joint is very appealing, but as jparkhur notes, requires a very precise cutting setup, expensive router bits and is a lot more time consuming.

Steve

jparkhur · « **Reply #6 on:** 23 Feb 2013, 02:38 pm »

I have seen many people in AC use the above method. Butt joints with a recess for the round over solid piece and then veneer the flat sides and front. Stain to match

jparkhur · « **Reply #7 on:** 23 Feb 2013, 02:40 pm »

Steve

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Quote from: srb on 23 Feb 2013, 02:38 pm

A 45 degree lock miter joint is very appealing, but as jparkhur notes, requires a very precise cutting setup, expensive router bits and is a lot more time consuming.

Steve

I tried the locking one and it did not go as planned. Totem uses it in most of their speakers. It's great if your great

pecker · « **Reply #8 on:** 23 Feb 2013, 02:43 pm »

You van even skip the solid wood, if your veneer is accomodating, and just apply it ove a round edged mdf panel.
Then cut your bevels and join the box together.

NeilT · « **Reply #9 on:** 23 Feb 2013, 05:56 pm »

Butt joints are easier to cut and assemble. Clamping up a mitered joint is very challenging.
Like jparkhur said, butt joints allow for pocket screws.

Neil

gregfisk · « **Reply #10 on:** 23 Feb 2013, 06:04 pm »

I thought I knew the names of all the different screws, but what is a pocket screw? Nothing like pocket pool I hope

srb · « **Reply #11 on:** 23 Feb 2013, 06:54 pm »

Quote from: gregfisk on 23 Feb 2013, 06:04 pm

I thought I knew the names of all the different screws, but what is a pocket screw? Nothing like pocket pool I hope

It's a quick and easy type of joinery that uses a screw flush driven into an angled hole or "pocket".

There are several jigs available to easily and accurately drill the hole, the most popular probably being the Kreg.

Steve

jackman · « **Reply #12 on:** 23 Feb 2013, 07:28 pm »

Is there a particular type of glue you guys recommend?

gregfisk · « **Reply #13 on:** 23 Feb 2013, 07:42 pm »

Thanks Steve, so the screw itself isn't unique other than it's long and thin? I installed a dishwasher at my beach house last summer and that is the technique that was used to put the cabinets together. It looks like they used soap or wax or something to help the screws go in as they looked like #6 screws and probably 3" long. I snapped off a couple of them trying to get them out.

WireNut · « **Reply #14 on:** 23 Feb 2013, 07:53 pm »

This is awesome stuff not only as a two part epoxy but also as a gap filler. It will make joints solid as a rock and void imperfections or gaps in the wood caused by saw cuts ext.

http://www.audiocircle.com/index.php?topic=114175.msg1191413#msg1191413

srb · « **Reply #15 on:** 23 Feb 2013, 07:58 pm »

Quote from: gregfisk on 23 Feb 2013, 07:42 pm

Thanks Steve, so the screw itself isn't unique other than it's long and thin? I installed a dishwasher at my beach house last summer and that is the technique that was used to put the cabinets together. It looks like they used soap or wax or something to help the screws go in as they looked like #6 screws and probably 3" long. I snapped off a couple of them trying to get them out.

Although I've seen it done with ordinary drywall screws, the angled shoulder of the screwhead is more likely to split the wood. Kreg offers washer head screws for softwoods and pan head screws with smaller heads for hardwoods. Both have square drive heads to prevent slipping.

Paraffin wax is always a good idea particularly for hardwoods or dense MDF.

Kreg also offers wood plugs to plug the holes and plastic plugs for laminate when the pocket will be exposed.

Steve

WireNut · « **Reply #16 on:** 23 Feb 2013, 08:11 pm »

decal · « **Reply #17 on:** 23 Feb 2013, 08:19 pm »

Check out Daedalus speakers to see some nice joinery.

rajacat · « **Reply #18 on:** 23 Feb 2013, 08:32 pm »

I've used a biscuit joiner to build kitchen cabinets and will soon use one for my diy speaker boxes. The biscuits help line up the edges and corners and add a lot of strength because of the added glue area. You do need a bunch of pipe clamps. OTOH after they're clamped up you can add screws to hold in place while drying and remove the clamps and move to the next panel. The screws aren't necessary for strength. You can use biscuits for miter joints too.

srb · « **Reply #19 on:** 23 Feb 2013, 08:50 pm »

The nice thing about biscuit joints is that the special beechwood biscuits are designed to swell and expand with wood glue and make for an extremely tight joint.

Steve