How to assemble a speaker cabinet?

[fvoelling]

OK, time to take a break from my shed building and put together my sub. I've got all the parts cut out, with perfect circles and all, and they are pretty close to being even in size, but how do you glue them together in perfect alignment? I have clamps, even a biscuit joiner (never used), but I've never put together a box, just two boards in a 90 degree angle, that's it.

I suppose dealing with one glue joint at a time could do the trick, but that sounds like a rather tedious affair. The biscuit joiner might help, but there's still play in the biscuits to deal with.

Any tricks or helpful tools/jigs for this?

Thx,
Frank

[opt-e]

You might find the following sites helpful:

http://www.users.bigpond.com/bcolliso/speaker-building.htm

http://www.speakerbuilder.net/web_files/Projects/D3/D3W/walk1.html

[RobP]

Do you have access to a router table? If so Sommerfeld has a nice 1/4" tounge and groove set that ensures perfect edges and and very tight joints. I also use a pocket hole jig made by Kreg tool, you can create super strong joints with pocket screws and glue, no clamps needed. I have never built a speaker cabinet with the pocket hole jig, but I have used it on cabinets and various other projects. Here are the links to the two.

http://www.sommerfeldtools.com/products.asp?id=202

http://www.kregtool.com/

[RobP]

Ill see if I can make a few joints using both methods tomorrow and post pics to give you an idea.

[fvoelling]

opt-e, thx for the links, I'll check them out tonight.

Robert, I do have a router table, but not the T&G set (but here's my excuse to get one . Not sure about the Kreg pocket hole jig, I'm working with 3/4" MDF.

[Jack Gilvey]

Given accurate cuts, simple butt joints work perfectly. Biscuits, hole jigs, T/G, etc. do help alignment in the absence of adequate clamps.

[FlashJim]

I love my Kreg kit. It's my second. I sold my old one when the new one came out.

[dyazdani]

I used butt joints and corner clamps to get things going. After a couple of sides were glued, I didn't need the corner clamps and just stick with regular bar clamps.

Everything lined up great, just had some minor Bondo/flush trim work to do at the end.

[Jack Gilvey]

I bought a few Bessey K-Body clamps at Sears years ago when they were closing them out (still pricey) and they've proven invaluable in getting the first four sides squared up (I tend to do that part all at once).



For the remaining two sides, I cheat a bit by cutting them oversized, gluing up, then flush-routing the edges perfect after it's dried. I forget who taught me that...maybe Brain Bunge.

[fvoelling]

Thanks for the suggestions, guys!

I like the idea of oversizing the last 2 pieces and flush-trimming them afterwards (too late for this project). For the first 4 sides, I suppose something like this would do the trick:




Oh well, maybe next time! I'll try my luck using the workbench's vice and some K-clamps.

BTW, one of the links opt-e posted mentions to use "neutral cure silicone" to seal the seams internally as regular silicone emits a gas that may damage the electronics!?

[JonW]

So you guys seem to think butt joints are OK? For my first speaker building project I was thinking about trying to cut rabbets into the edges of the panels. To hold thing together a little better. I've never tried anything with a rabbet before,though. Worth the effort or don't bother?

[chasw98]

So you guys seem to think butt joints are OK? For my first speaker building project I was thinking about trying to cut rabbets into the edges of the panels. To hold thing together a little better. I've never tried anything with a rabbet before,though. Worth the effort or don't bother?

Jon:
I've done both. With enough "clampage", butt joints work just fine. You definitely need to dry assemble first and check your edges. I have also used the cut em a little large and flush trim afterwards technique. Of course, people with 10 horse delta saws and motorized feed trays with super fences just cut and build. But we have to measure twice and cut once and then checkit again. Just make sure joints are square when you do start glueing it up. :T

[opt-e]

BTW, one of the links opt-e posted mentions to use "neutral cure silicone" to seal the seams internally as regular silicone emits a gas that may damage the electronics!?

From what I've read, any silicon is okay as long as you let it dry/cure completely before inserting any electronics/drivers into your box. I could be wrong though, so hopefully someone will correct me if that is the case.

[ThomasW]

Just use standard Alex Plus siliconized acrylic caulk to seal the internal seams. It's available at all the big box building stores.

[---k---]

Just don't use clear caulk! You can't see it inside a dark box!

[Jack Gilvey]

BTW, one of the links opt-e posted mentions to use "neutral cure silicone" to seal the seams internally as regular silicone emits a gas that may damage the electronics!?

If you're concerned about gaps, you can also use polyurethane glue (Gorilla Glue) which expands as it cures and skip the caulking step. I used to use this, but since I got my table saw I just use Titebond or Elmers wood glue with no caulk step and I have no leaks.

[fvoelling]

OK, got the box glued together, sanded (and sanded, and sanded - I got a bit overzealous with the glue), screwed in the amp and driver, hooked it up, and voila, it not only works, but sounds great!

Thanks everybody who helped along the way!

A couple more questions. Is there any science on how to set the volume of the sub amp for integration with the main speakers' amp, or is that a matter of personal preference?

About the finishing! Honestly, I probably would have left it unfinished (MDF) since I had it all hooked up, stashed away underneath my desk, and it finally allowed me to really enjoy my Maggies.

Well, my teenage son was just dying to employ his latest painting technique that he used on a model car and decided to spray paint it gold followed by black (on his model car the gold shimmered through the black). Then he sprayed a clear coat on top. Unfortunately, neither one of us discovered until after the fact that the gold paint was for metal surfaces only, and even though he had sprayed it with primer first, it kind of messed up the whole thing.

We've since sanded it again (lightly to rough up the surface a bit) and oversprayed with a matte black paint, but it looks pretty uneven (dull in most spots, some shiny or rough probably due to insufficient sanding, etc). Also, you can take a paper towel and wipe it and be left with residue paint on the towel even after letting the paint dry for almost 20 hrs now.

What's the best thing to salvage this and end up with a semi-decent black finish?

Thx,
Frank

[cgr]

I used the duplicolor truck bedliner on my sub. You probably want to rough up the existing finish enough so that any primer will get a good bond first before using the bedliner.

The speaker in this thread uses the same bedliner for it's finish: http://www.htguide.com/forum/showthr...ight=ascendant

[fvoelling]

Thanks, that bedliner stuff is fantastic!!!

Anybody have some guidelines on how to set the sub's volume level vis-a-vis the main speakers'?