DIY Fiberglass Tower Speakers

[d_coyne1984]

Here are the pictures first.

Edited by txav8r to who full image.

 

[Bruce]

Great Job!

I accidentally disliked your post. I clicked the wrong button. Please accept my apology. @Julian moved dislike to the other end so that accidental dislikes will be reduced.

 

[Julian]

Damn....those look Professional level quality! NICE!

 

[txav8r]

Those do look dang good! Did you design them with a specific interior size for optimum sound quality?

 

[d_coyne1984]

Materials:

• Carboard
• 1/2" MDF
• Countersink drill bit
• 3/4" #6 or 8 wood screws
• Wood Glue
• fleece material with some elasticity
• general purpose clamps (for holding wood together while glue dries)
• Staples and staple gun
• 2- Tower clamps (http://www.globaltruss.com/ProductDetails.aspx?ItemNumber=529&MainId=9&Category=16)
  
• 2- 1/4-20 hex head bolts
• 4 - Large Fender Washers
• 2 - Split-lock washers
• 4 - 1/4-20 nuts
• One gallon of fiberglass resign with hardener.
• Lots of disposable paint brushes
• Bondo

This was my first attempt at fiberglassing so these are kind of crude and only my first attempt, but I am fairly happy with how they turned out and sound. I started out by making a pattern out of cardboard since I wanted two identical pods. One round speaker frame which I sized by tracing the speaker grill and two "U" shaped rear supports that I just drew by hand using the proper width and matching length for both pieces. I traced the pattern onto 1/2" MDF and cut it out with a scroll saw. I made opposing notches where the rear pieces fit together rather than breaking the rear structure into 3 pieces. I predrilled both the face frame and the rear structure, but I still had a little bit of splitting on the rear structure because I probably didn't go big enough on the bit size, but between the screws and the wood glue, it all held pretty solidly. Oh, and I forgot to mention that I made the top support triple thick for mounting strength. To do that I just traced the "U" piece that creates the top and bottom rib, and just duplicated the top part (one 1/2" piece on each side of the top support. I screwed and glued those together too.

I then wrapped the surface in a stretchy fleece that I got from Joan Fabric. Kind of a bitch to work with, but I thought heavier fabric would be better (I'll explain more on this later). I used a hand operated staple gun and wrapped the frame from the back towards the speaker frame, stapling the fleece on the front of the frame and along the top (main support) rib. I coated the boxes with two coats of fiberglass resign on the outside, one on the inside, and covered the inside with 4x4" pieces of fiberglass mat with a coat of resign obviously over that. No matter what fabric you use, make sure all the fabric is completely soaked with resign otherwise you will have soft spots. I sanded the exterior to try and get it a little smoother before adding a 3rd coat to the exterior of the box. I sanded that a little before smearing bondo over the box to fill the low spots and pits, sanded, and repeated a few times until my give-a-damn broke.

I predrilled the speaker screw holes and did a temporary install and fit of the speakers so that I could roughly figure out where the balancing point of the loaded enclosure would be. I drilled a 9/16" hole through the top rib and installed the tower clamps with a 1/4-20 bolt. I used a large fender washer between the clamp and the box, one more inside the box, a split washer (lock washer), and two back to back nuts.

For the speaker terminals I just bought some fairly inexpensive units on Amazon, and drilled and fastened them into place before the final speaker install. The clamps I used were from global truss. They are an aluminum quick release (I don't leave the speakers mounted while towing) clamp designed for mounting DJ lighting to truss systems. They are a 50mm (or 1.96") so what I did to make them fit nice and not chafe the tower is add 1/8" weather stripping from home depot and they fit super solidly. Even better than I had hoped. They are only about $15/ea so WAY cheaper than buying the advertised speaker mounts. That will teach those fuckers to try and rape my wallet.

I ended up using a can of bedliner spray after I gave up on trying to get the boxes smooth enough to do a polished finish. I figured if it's going to be rough, I might as well make it look like I planned it that way.


Lessons learned:

• The fleece I used was way to heavy. I ended up not getting the top of one of the boxes completely saturated and when I installed the clamp it squished a little in order to get it tight. It was a pain in the ass to try to cover the frames uniformly. It also resulted in me wanting to pull my hair out while trying to get the exteriors smooth and to an automotive finish. Bondo and resign drys very quickly so it's kind of a bitch of a learning curve to work with. I would recommend using something more like a nylon material that would saturate very easily with thin coats and plan on doing a few layers of fiberglass on the inside to get your strength.
• Pay close attention to box volume. Most automotive speakers are designed to have a decent amount of air volume behind them. I chose 6x9's because of their lower overhead profile to size ratio and their generally higher power handling capabilities vs say a 6 1/2" woofer. I don't have dimensions handy, but I made them to a fairly good size, but was still pretty disappointed in the lack of low end for being a 6x9. I contacted Polk and they said that the bass is very likely being choked because of the very limited air volume and that those speakers aren't designed for sealed enclosures (Woops). I decided that sound quality was more important than complete water proofing so I drilled two 1" holes in the back end of each box for the speaker to breath. I finished the holes by inserting a 1" snap-in electrical bushing. They still don't have the low end that they would if installed in the back deck of a car, but it was a drastic improvement.
• I wish I would have added ribs between the existing ones to push the box volume out a little more. I think aesthetically they would have looked even cooler too.

 

[d_coyne1984]

@txav8r

Those do look dang good! Did you design them with a specific interior size for optimum sound quality?

Yeah, no I screwed up on the size. I really thought they would have enough volume, but I was wrong.

 

[txav8r]

Nothing beats the satisfaction of doing it yourself! Thank you for sharing your lessons learned too, that will certainly let anyone using this thread as reference, that planning may save some disappointments. Are you going to rebuild them to get the sound your after? It may not be your enclosure as much as it is an "open air" arena your playing to and losing the bass in the open air. @Julian , do you want to put this in the FAQ? It would be helpful I am sure! Thanks again for the time to create this thread and your sharing!

 

[Julian]

Added to the FAQ under Stereo/Electronics #10

 

[dustinjean]

looks good i almost built my cans and an led setup but got too good of a deal on kicker cans to spend my time making some

 

[d_coyne1984]

@dustinjean
Where did you find your deal?

 

[dustinjean]

@d_coyne1984 perks from a previous job straight from kicker, got about $2500 in stuff for well under $1000

 

[d_coyne1984]

Dang! Know any insiders that could hook a brother up? Lol! I love job perks. I wish I had good ones.

 

[dustinjean]

i wish i did because a friend needs some stuff too