My Titan-39 build

[billkatz]

Thanks for the advice - I decided to bring cabinet 2 up to "everything but the final side", and then paint the insides of both. The braces are sturdy, I picked up the cabinet by a couple braces tonight. That PL is strong! I've made good progress on cabinet two this week - I installed the 4 driver flanges, the 4 little braces, 2 panel 7s, as well as panels 8,9, and 10.

Now I just need to add panel 11 and the 6/10 braces and cab 2 will be caught up to cab 1.

[billkatz]

I got panel 11 in a while ago, and tonight I installed the 6/10 braces and cross brace. My 6/10 braces were off a bit, but another 1/2 degree on the Excalibur table, and they fit perfectly! I've also done some work at the joints with my belt sander. I just need to paint the inside of the cabinets, and they'll be ready for the second side. Then all that finishing work.

A couple questions about the second side:

1) I expect that an extra wide bead of PL is appropriate here?

2) Even though I've used nothing but 18 gauge brads so far, are screws recommended on the inner horn parts? (I'm lazy and trying to minimize the whole bondo/sanding stage)

I'm getting close to really needing a Driverack and amplifier...

[djtrumptight]

A regular bead of PL will do,as long as you get squeeze out but dont take my word for it,i used 5 1/2 tubes of PL on my last 2 T-48's.

From the plans: "this is where screws work best,to pull the second side in tight".

[billkatz]

I finally got some time today to do some work, and painted the horn mouths, in anticipation of putting the second sides on. Some quality time with my Duratex roller.

[Jools4001]

I'm lazy and trying to minimize the whole bondo/sanding stage

Me too. I bought some bondo, better known as body filler over here, from the local car accessories place because it said "Sands Like Magic" on the tin. So I put it all over the screw holes and imperfections, then left it overnight, expecting that Mickey Mouse would show up dancing around to the Fantasia theme, or at the very least some shoemakers elves would get to work, but alas, in the morning it was still the same mess and I had to do it myself!

Mind you, a random orbital sander makes quicker work of it than Mickey.

[billkatz]

I've got a belt sander, but it might be a little too aggressive for body filler...

I took the plunge tonight and put on the second side. It lined up pretty well, and the line I drew on it back at the beginning were right on. I dry fit it with a bunch of screws, and then added a liberal bead of PL everywhere. Squeeze out looks good.

Using the screw reminded how much easier the brad nailer is! I shot a few brads in each panel to make sure everything was nice and tight while the PL sets.

Any recommendations on what round-off bit to use on the outside? I have both 3/8" and 1/2".

Do people bother with the body filler on the brads? Or will Duratex hide those well enough?

I feel like I'm getting close to actually hearing something from this cab...

[dswpro]

Duratex covered my brad holes just fine.

[MissileCrisis]

Half the time I spent building my T60 was setting up or inserting screws in the panels. I didn't count but I know it was over 120, and each were countersunk/predrilled. Next build I'll probably get a brad nailer, especially if I'm doing it solo, I am a firm believer in never build alone if given the opportunity to have an extra set of hands. They don't have to know what's going on (nice if they do) but 4 hands are priceless.

[billkatz]

Tonight I sanded, bondoed, and sanded the first T39. I used a belt sander to even things out around the edges, took out the screws from the final side, and filled the holes with bondo. Using the brad gun on all but the final side made this step go pretty well - only 9 holes, and I got them all with one batch of bondo before it hardened.

Then I rounded over all of the edges. Here's that final side:

The cabinet really looks like a cabinet now! I think I'll put on the duratex next, then mount the driver and finish the access cover brace, and then put all of the corner hardware and casters on. Of course I need to break in the driver. (I think I can use my son's bass amp for that) However I won't be able to listen to anything until I buy the proper crossover/limiter and a reasonable amp. And I can't do anything useful until I finish those DRs!

Here's a front view of the cab, ready for paint:

Another question: The plans say to install the access cover with either screws or bolts with blind nuts. The screws sound easier, but the blind nuts give me more confidence I can re-seal the panel if I ever have to take it off. What have others done?

[miked]

Billkatz: Isn't it nice to put the roundovers on the cab? Makes it look like a real cab, at last! Good stuff.

The large, plastic corners have a 1/2" radius, but 3/8" works very well too. I used 3/8" on all my cabs and you can't tell that they're not a 1/2" radius as the corners fit perfectly. I've found that the 1/2" radius, while looking "this much nicer" can dig down too far and hit countersunk screws or brad nails. Bad for the router bit and bad for you if it tears out a chunk of plywood along with the nail. So 3/8" has worked well for me.

As for the access panel, yes, t-nuts are best, allowing you to remove/replace the cover with no worries about sealing. But really, how often will you remove the panel? And even if you replace a blown driver (which you shouldn't have to do if you limit properly) a few times during the life of the cab, COARSE THREAD drywall screws (I used 1.25" long ones) bite hard in plywood and you can always add more foam weather-stripping if you have trouble getting a seal.

In order to use t-nuts on the access panel, you really need to drill the holes and insert the nuts before construction starts, before you glue the flange strips (or 1-piece flange) into the cab. Sure, you CAN get tnuts in there now, but how to line them up with the bolt holes in the access panel...which you probably haven't drilled yet?

Here's what I did:

1. Before adding weather stripping to the flange, determine the center line on your flange pieces. IIRC, my flange is 1.5" wide, so 3/4" is the center line
2. Mark that center line on your access cover, all the way around. Mark where your screws will go. Use enough screws!
3. Lay the access panel in it's place on the cab, ensuring it is centered in the opening.
4. Hold access panel down firmly. Drill two small pilot holes opposite each other through the access panel and flange. Drive two screws through those two holes. The access panel is now screwed down and won't move. Drill the rest of your pilot holes.
5. Repeat for other cabs
6. Remove access panel. Vacuum out all the sawdust from drilling the holes!
7. Using the drilled pilot holes as a guide put a row of 1/2" weatherstripping on either side of the row of holes. Now when you screw down the cover you have a double seal, on either side of the screws, sealing your driver chamber.

I am OCD about these things, so I take what some might think are "unnecessary steps" but it works for me.

ps
Important! If building more than one cab, it is unlikely that you will drill all the access cover screw holes in the exact same spot on all cabs. I labeled the driver chamber and inside of the access panel with matching numbers. Cab1/Lid1, Cab2/Lid2, etc.

[byacey]

In order to use t-nuts on the access panel, you really need to drill the holes and insert the nuts before construction starts, before you glue the flange strips (or 1-piece flange) into the cab. Sure, you CAN get tnuts in there now, but how to line them up with the bolt holes in the access panel...which you probably haven't drilled yet?

A simple solution is to install the T nuts and then take some machine screws of the appropriate thread, and cut the heads off. Thread them into the T nuts so about 1/4 to 3/8 of an inch is protruding out the front; try and make them all stick out by the same amount. Rub some colored chalk on the ends of the the screws and gently press the access cover into place. The chalk will mark where you need to drill. If a few didn't mark, remove the machine screws from the others that did mark properly and repeat the chalking procedure.

Resist the temptation of making indentation marks by thumping on the access cover; if you didn't do a good job of making the T nuts captive, you'll be sorry after driving them out the backside.

It sounds like a lot of work, but once you have the heads removed from the screws, it's about 1 minute of work to accurately mark all the holes.

[miked]

Now that's a great idea, byacey. Well done! I'm glad that you put the "don't thump on the cover" disclaimer b/c that's pretty much what I'd probably do. LOL!

[Bruce Weldy]

I just position the cover where I want it, then drill a pilot hole all the way through both panels. Then it's lined up. No marking necessary.

[Bill Fitzmaurice]

I just position the cover where I want it, then drill a pilot hole all the way through both panels. Then it's lined up. No marking necessary.

+1, though I put a nail through the first two holes drilled to keep the panel from wandering when drilling the rest of the holes.

[billkatz]

I just position the cover where I want it, then drill a pilot hole all the way through both panels. Then it's lined up. No marking necessary.

+1, though I put a nail through the first two holes drilled to keep the panel from wandering when drilling the rest of the holes.

Well, it has ben many months (did we really discuss the access cover last June?) since I worked on my T39s, as I've been busy with the DR250s. But today some glue had to dry on the DR, so I came back to the Titan. At this point finishing one Titan and one DR will be great for my son's graduation party later this spring. I now have a driverack and just bought a used mixer. Speaker stands for the DRs and an amp will let me fire the system up!

The first thing I realized (while I was mounting the woofer on the DR) was that I really should have drilled pilot holes for the woofer before putting the front flanges on the cabinet. However a trip to the hardware store came up with this beauty:

a 6" long 1/16" diameter drill bit! With that (and only a tiny bit of relief with the Dremel) I was able to drill pilot holes, and run the Recex screws in and out of the woofer mounting holes. I think I'm ready for the woofer. Then I turned my attention to the access cover. I decided on 10-32 oval hex-head screws and hurricane nuts. as Bruce and Bill suggested I drilled one hole, put a nail in, drilled a hole in the opposite corner, added a second nail, and then drilled pilot holes. I chose 14 screws with the sides just under 4" apart and the top/bottom 3 1/4" apart. I then drilled all of the holes bigger to clear the 10-32 screws, and then enlarged the holes in the flange to the 1/4" required for the hurricane nuts. I pulled in the hurricane nuts with the cover off, and everything lined up perfectly. I also cut out the cover braces today.

here's the cover on with all the screws in (no gasket tape yet).

Next up is a coat of Duratex.

Any suggestions on how to get the front painted in such a way that:
a) the hurricane threads don't get jammed with paint
b) the screws don't get their sockets jammed with paint
c) everything gets painted

After the Duratex I just need to mount the driver, jack plate, wheels and corners.