Tuba30 + SLA Pro

[SirNickity]

I started my build about a week ago, but just got the pictures developed. (By that, of course, I mean plugging in the USB cable.) So here goes.

The project at hand is a pair of Tuba 30s, about 20" wide, with Eminence 3012LF drivers. For tops, a pair of SLA Pros loaded with 4x Eminence Alpha 6Cs and the 6x piezo array. The SLAs will be interesting -- I have some modifications in mind there, but I'll get back to that.

I bought the plans a year ago, and started collecting tools. I had a little B&D Firestorm cordless tool pack (drill, circular saw, jigsaw, light, and useless vacuum cleaner), but that's about it. I've had exactly one wood project to get my feet wet. Before that, the only thing I had made out of wood was a fire. So, bear in mind, when Bill says the plans are made with the assumption you are not an expert woodworker, well.. I'm the practical application of that theory.

I'm using a timeline approach to give you a sense of how long it takes to build these things.

Day 1

I am NOT a morning person, so I got a late start on the Memorial Day weekend Saturday, and spent the afternoon drawing up my cutsheets. I bought four 5x5 Baltic Birch panels before measuring everything out. I figured that would be enough to get me through the weekend at least. Turns out, I was just a little short -- one 30x30 side panel. No big deal, as I still needed wood for the SLAs, so I bought another two sheets later.

Progress was slow at first. I ran to the hardware store to get better saw blades for the table saw and the cordless circular saw -- I was still using the cheap factory blades in both. While I was there, I got some plastic sawhorses / work surfaces, and a couple garage door opener hangers. These are 36" long steel stock with a 90-degree angle. They turned out to be a cheap and effective saw / router fence, as they could be clamped down or screwed down through the holes. If I were starting over, I would've gotten one 36" long one, and another twice the length to go across the sheets, instead of having to use two end-to-end.

Unfortunately, there's no way a 5x5 sheet will fit on my table saw, so I had to prop them up on the sawhorses and do the initial rips with the circular saw. After my second cut, I managed to knock the saw off the wood and onto the concrete floor, hopelessly ruining the shoe alignment and prompting a second trip to the hardware store. That's fine, I was having doubts about the feasibility of battery-powered tools for this project anyway.

$40 got me a 12A Ryobi circular saw. Another $13 got me another Freud Diablo blade. Seriously worth the bread, folks. Replacing the one in my table saw ($37 for that one) made it much quieter, it doesn't tend to flex and wander, and it slices through the wood like a hot knife in butter.

So after a few false starts, I ended the day at 2am with a stack of panels, and the garage and myself covered in saw dust.

[SirNickity]

Day 2

I had just ordered the Tuba 30 kits from Speaker Hardware a couple weeks before, after taking on an outdoor DJ gig scheduled for June 15th. I have a PA system already, of course, but I have serious doubts that a Peavey SP118 (1x18) sub can pull it off alone. On top of that, there are three areas that need sound -- one indoor hall (a pair of powered monitors will cover that), the main field (maybe about an acre? I'm not totally sure), and a gazebo with a barbeque pit off to the side, where my old PA setup will go. It doesn't have to be loud, but I want it to be enough.

I have the equipment because I used to tool around in a band, and house PA is always lacking. I kept getting asked to DJ for events (mostly friends and family weddings, company Christmas parties, that sort of thing), so I picked up a Traktor S4 to make life a little easier. I'm steadily building up a music library, and so far I've gotten great feedback. I still invest more than I make, but to be honest, I'd buy the toys anyway, so may as well see some return on it.

Well, back to the garage. Four weeks to finish the new kit. Totally doable. (I hope.)

Day 2 was mostly prep-work. I got the plans stapled up on a sheet of OSB, drew the guide lines on the side panels, and got some hands-on time with the router.

First picture is of the side panel, with all the 1/2" dado grooves. I found this really helpful for lining up the panels. I chose a depth of about 1/4" -- or more precisely, half the plies. For a newbie just learning the ropes, my second attempt was a little better, after learning how to control the router and go with the bit rotation. It took a couple hours to get all of it done -- someone with experience would go much faster, but this isn't a race.

The next picture is with two panels in place. This is a great feeling, seeing the parts fit together and nice, flush angles. You can't help but feel a little pride, staring back at it before throwing in the towel for the day.

[SirNickity]

Days 3, 4, and 5

The next day was after work, so no more noon-to-AM workfests. Adding to that, I had gotten to panel 3 -- the baffle. The single most labor-intensive inside panel. I downloaded the driver spec sheet, made some measurements, and found I had no good way of cutting a perfect circle, so I had to make a jig.

The jig picture shows what I came up with. Just your basic radius around a center point trick really, nothing new or novel. This falls squarely under "if it looks stupid, but works, it ain't stupid." It went rather well, resulting in an almost perfect circle. (I found that I needed to add a shim between the router plate and the stop plate to keep the router from wiggling.)

The mounting holes are a real chore. There's so little room for error here, and it's the last thing I did before gluing in the panel, that I was getting a bit stressed that I would screw it up and have to start over. Turns out, it wasn't perfect -- I had to drill out two of the bolt holes a little in the driver basket. *sigh* I hope I never have to field-swap drivers.

The second picture is my table saw prepped for hurricane nut surgery. I was starting to feel a little like Dexter.

That was Day 3 -- already past my bedtime. So close ...

I picked it up the next day, testing the edge clearance during excursion -- so far so good. Finally got to install the panel, then number 4. It felt good to see them falling into place a little more quickly.

Another evening gone, onto day 5, bringing panels 5 and 6, and the first braces. I ended up marking the end lengths on a scrap piece of wood, then using a chop saw to cut the angled part. This worked pretty well, and seemed much easier than trying to work out a miter on the table saw, or setting up some kind of jig with the circular saw.

I didn't want to stress the braces by working around them (I didn't use screws -- just glued them up and shoved 'em in place), so I called it an early night. Braces aren't glamorous panels for sure, but it is nice not having to be quite so precise. No worrying about straight angles or exact measurements and all that..

[67baja]

Coming together nicely! Keep up the good work.

[bitSmasher]

Good read, well documented - thanks!

Interesting that as a self confessed n00b you opted to dado the joints. What method did you use to guide the router for this?

[subharmonic]

Looking like a good start.

[thekl0wn]

Hey, I'm doin' pretty much the exact build right now! Everything looks great so far!

[SirNickity]

Interesting that as a self confessed n00b you opted to dado the joints. What method did you use to guide the router for this?

I figured that it would actually make things easier in the long run. The grooves hold the panel in place, and keep any minor warps under control while the screws are being driven in from the other side, so it's actually more newbie-friendly than not doing it, in my opinion. A better woodworker would be able to anticipate and correct things like this, and know better how to use clamping and guide boards, whereas I'm likely to make a mess of things.

All in all, the learning curve for the tools so far has been very gentle. They're not hard to use, just takes practice to do it well. At any rate, I knew I'd be using the router for cutting speaker holes and any recessed handles or jack plates later on, so may as well get used to it!

As for guiding the router, I used the garage door hangers. Basically an L shaped piece of metal stock. In the second post, in the picture of panels 1 & 2 glued in, you can see it in the bottom right, on the floor. I measured the distance between the edge of the dado bit to the flat side of my router base, then drew guide lines that same distance away from the edge of all the panel lines. (See the attached picture. It's faint -- open the full-size image for a better look.)

Then, I clamped the metal so it was flush against the guide line to make the fence. You know those thin, floppy metal rulers with the cork on the back? I put one of those flat against the perpendicular fence edge, so the edge of the ruler was riding along the guideline, then adjusted the fence until the ruler followed the guideline precisely. That pretty much ensured the router would be aligned correctly.

Sorry if the description is a bit verbose. Hoping maybe some other new guy can take advantage of a couple tricks I learned along the way.

[SirNickity]

Day 6

Another Saturday. With an entire day to work, these things move along nicely. Makes me wonder why I bother during the week.

First things first -- got the two extra sheets of BB cut, giving me the top panel of the second T30, and all the parts for the SLA Pros.

Look! SLA Pros!

With the last piece cut for the T30, I could finally trace and drill the pilot holes, and start gluing panels. The process is pretty gruesome. First, I space the the pilot holes out along the dado groove, then dry fit (clamping as necessary) the panel in place. From underneath, I drill the pilot hole up into the side of the panel, and chase it with a screw. Three to five screws does the trick. Then, any adjacent / intersecting panels get screwed in place as well. At this point, the panel is going nowhere, so the clamps can come off. After a once-over to make sure everything's kosher, I pull the screws, slather PL all over the edges, then screw it back together.

My forearm is killing me. But, by the end of the day, there's significant progress:

Seeing double.

[SirNickity]

Day 7

The outside panels are not fun. They're so big, there's guaranteed to be some warpage. They don't join other panels quite so often, so you can't rely on existing structure to pull them in place. I ended up shimming the bottom of the work table to make it completely even, then using a level to ensure the panels were straight up and down. At least, as close as I can get.

Agghh.. SO close.

Along those edges, the PL oozes out of the side like melted caramels. On a paper towel, it's like motor oil. You can never really wipe it off completely. Impossible to get through this without sticky hands. I have some citrus scrub cleaner meant for stripping oil and grime off hands, and it works well for taking that sticky residue off.

Slowest. Drip. Ever.

It occurred to me that if I put the braces in before putting the next outside panel on, I might end up pushing the panel out (or pulling it in), so I dry-fit panel 10 to get the corner edges to align first. Of course now, it's not so easy to get the braces in, since the only access is from the side of the horn path. Good thing those inside braces don't have to be pretty. I got PL everywhere, and who knows if they're straight, but if I'm lucky, they'll never see the light of day again anyway.

I think I found a bug on panel 10:

100% organic.

And another weekend gone. Less than two weeks til showtime.

[67baja]

I often screw/glue braces to the panels (after I confirm I have the braces cut okay) to each outside panels, then glue/screw the panels in place, using pl to hold the braces to the inside panels. It is easier to me than trying to slide the braces to their proper location and screw/nail/glue them AFTER the outer panel is installed.

[SirNickity]

I might have to switch to something like that on the outside panels. The inner ones are easy enough -- they're small and short and slip right into place. It tends to get messy with the ones over 10 inches, though.

Day 8

After all the construction, it seemed like a good time to cut some holes, so I went for the corner handle and jack plates. The placement of the jacks dictates somewhat where my panel 10 braces are going to go, so it's holding up progress anyway.

An air leak waiting to happen.

With a tight schedule, I have no patience for air leaks, so I'm doing everything I can to prevent them in advance. Unfortunately, the corner handle protrudes THROUGH the panel 9 brace, so I can no longer take advantage of that little chamber being air tight.

An air leak happening.

The solution: An isolation box! A frame of thin scraps of plywood, with a flat piece behind it. Have a montage:

It's a montage!

That took most of my time for the night, so I glued in panel 10 and dry-fit panel 12 on the first sub, glued in panel 6 to the second one, and closed up shop.

Not much to show for the night.

[doncolga]

I was wondering about that on my T30's and decided to hold off on cutting out holes for those handles.

[SirNickity]

Day 9

Now, I guess you can leave the jack plate bare, use the gasket, and the Speakon jacks should be relatively airtight -- or so I'm led to believe. But I'm not taking chances there. So, I devised another isolation box for the jacks:

Isolation box mock-up.

This is just the panel 1/10 brace with some scrap ply on top of it. Panel 10 will form the front, with the jack hole in the middle, and the second brace will form the top. Like so:

Dry-fit with both braces.

Here's a test-fit around the jack plate hole, showing the clearance for the terminals. It should be a straight shot into the driver chamber for the speaker wire, and I can put in some loose clips to hold the wires in place. I think I'll avoid cinching it down, just in case I ever have to replace that wire, but something to keep it from flailing around would be nice.

Success!

From the outside, with both jacks and corner handle in place (but not yet mounted.)

It all fits.

Yet another day while the iso block dries...

"I have too many clamps." -- No-one.

Panel 7 installed on sub 2. No nightly status shot -- too many pictures in this post.

[SirNickity]

I was wondering about that on my T30's and decided to hold off on cutting out holes for those handles.

Another solution might be just to move the brace out by 3/4" or so. From what Bill has said in the past, the placement isn't critical, it's just there to reinforce the structure along the corners. Too late for me, though. I had already routed out the dado grooves by the time I checked for fit. The iso box wasn't bad -- it took more time to find a combination of tools to cut the holes than it took to assemble.

(BTW, circular saw for the initial cut into the corner along the hole's edge lines, then router to plunge holes in the corners of the piece to be removed, where I could then fit the jig saw to rough out the area. Then I hand-guided the router with a 1/4" dado / trim bit to clean up the edge lines. Not the prettiest holes, but they'll do.)