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My First Build - Tall AutoTuba (TAT)

Posted: Wed Aug 29, 2012 9:48 pm
by kkip
I decided to build an 18" wide Tall AutoTuba for my first tuba project because of the small size and cost. I used one sheet of Arauco ACX plywood and selected a single 8" JBL GTO804 as the driver. Not really planning to use this in a car. It will probably serve as a small HT sub for now. Or maybe I will donate it to the youth band at my church. My son plays drums and has been promoting that idea. I started taking pictures kind of late in the project. But here is my progress so far:

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Well it's taken a good bit of time to get to this point. But it's starting to come together.

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I cut the sides and panels 1-5 using a circular saw. Then I came across this bad boy at a garage sale. Cutting the remain panels was much more fun!

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Adhesive applied, finally ready to install side two.

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All assembly complete, edges routed. Next step, fill holes and sand.

Re: My First Build - Tall AutoTuba (TAT)

Posted: Wed Aug 29, 2012 10:58 pm
by Lastcat
Looks good, nice build. Great score on the TS. :clap:

Re: My First Build - Tall AutoTuba (TAT)

Posted: Thu Aug 30, 2012 12:03 am
by Bas Gooiker
TAT is looking good. Doesnt look like its gonna fit any european cars though.

Damn i could use a table saw like that... :mrgreen:

Re: My First Build - Tall AutoTuba (TAT)

Posted: Thu Aug 30, 2012 7:57 am
by shawn_g
Nice work. Looks great!

Re: My First Build - Tall AutoTuba (TAT)

Posted: Thu Aug 30, 2012 8:02 am
by Bill Fitzmaurice
Bas Gooiker wrote:TAT is looking good. Doesnt look like its gonna fit any european cars though.
Even Europeans can't fit into European cars. :lol:

Re: My First Build - Tall AutoTuba (TAT)

Posted: Thu Aug 30, 2012 8:31 am
by Bas Gooiker
you'd be surprised...

Apologies for the hyjack of your thread here...

The Agony of The Spinning Nuts

Posted: Fri Aug 31, 2012 10:10 pm
by kkip
Thing started out good today. After filling the holes with Bondo and sanding everything down, I applied a coat of Kilz latex primer since there is still some PL here and there on the surface.

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I decided that it was time to install the driver. That is when things became a bit more challenging. After getting all of the screws started I began to tighten tthem. But then I discovered a problem. Apparently, the little dab of epoxy that I added to the hurricane nuts wasn't enough and I had not one, but two nuts turning, Ugh! Not good. Fortunately, the screws were right beside each other so I was able to lift the driver somewhat and clamp onto each nut. For the replacement nuts, I used a generous amount of PL instead of epoxy under the flange. I also went around and added PL around the flange of the remaining 6 nuts. Lesson learned. Next time I will use a generous amount of PL or epoxy on each nut. Also, I will lube the screws a bit and run them in and out a couple times to they will be less likely to bind up.

Next step will be to install the driver (again) and leak test. I will be applying Durtex as well as installing corner protectors and feet .

Re: My First Build - Tall AutoTuba (TAT)

Posted: Fri Aug 31, 2012 11:33 pm
by Drey Chennells
Nice job, the TAT is an awesome cab. Just a tip, when using T nuts PL will release metal in general, epoxy works better.

Re: My First Build - Tall AutoTuba (TAT)

Posted: Fri Aug 31, 2012 11:56 pm
by kkip
Drey Chennells wrote:Nice job, the TAT is an awesome cab. Just a tip, when using T nuts PL will release metal in general, epoxy works better.
Do you just use a general purpose 2 part epoxy? That is what I used but only a little dab on each nut before pressing it in. Thanks for the advice on the PL. Hopefully the amount that I used will hold this time.

Re: My First Build - Tall AutoTuba (TAT)

Posted: Sat Sep 01, 2012 1:33 am
by djtrumptight
The problem is you are pressing the T Nuts/hurricane nuts in,i did that on my 2nd T 48 and it has caused problems such as them spinning,me replacing them with wood screws that come loose and cause air leaks that cause blown drivers."PULL" them through according to the plans and as someone said,use 2 part epoxy,PL wont bind wood to metal.Ita also good to run a tap through the T nuts before installing bolts.

Re: My First Build - Tall AutoTuba (TAT)

Posted: Sat Sep 01, 2012 9:11 pm
by kkip
Thank for the feedback on the nuts. Next time I will definitely use a generous amount of epoxy and will pull the nuts through with a screw and large washer. Fortunately, my repair to my spinning nuts were successful. I spent a lot of time making sure that all of the bolts were loose and could be finger tightened. I carefully reinstalled the driver and everything went fine.

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I did a little preliminary testing and am pretty please with how it is working. My crossover/limiter is being repaired at the moment, So I used a 100 W plate amp for some basic testing. I ran the input up to about 10V which produced a very impressive output. I found some leaking around the access panel sealed so I have a little work to do on this.

Re: My First Build - Tall AutoTuba (TAT)

Posted: Sun Sep 02, 2012 7:21 am
by Drey Chennells
kkip wrote: I found some leaking around the access panel sealed so I have a little work to do on this.
If you're using regular wood screws here boring out the access panel pilot hole slightly larger than the screw threads will prevent stripping. The preferred hardware would be Leland's smooth shank screw for good pulling power.

Re: My First Build - Tall AutoTuba (TAT)

Posted: Sun Sep 02, 2012 10:45 am
by kkip
Drey Chennells wrote:If you're using regular wood screws here boring out the access panel pilot hole slightly larger than the screw threads will prevent stripping. The preferred hardware would be Leland's smooth shank screw for good pulling power.
Oh good advice. I don't have the final hardware for the access panel yet. Smooth shank screws sound like what I need.

Re: My First Build - Tall AutoTuba (TAT)

Posted: Tue Sep 04, 2012 9:44 pm
by kkip
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First coat of Duratex!

Re: My First Build - Tall AutoTuba (TAT)

Posted: Wed Sep 05, 2012 7:14 am
by shawn_g
Duratex makes everything look professional. Very nice.