Custom fiberglass sub enclosure is finally FINISHED !!

05cc4x4 said:

Looks good man. How difficult is it to get everything mixed right? The build and fabric look straight forward enough but I'm wondering how hard it is to mix the chemicals right.

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The resin for the glass is what I'm assuming you are asking about?
They all vary, but the hardener for this particular resin stated 14 drops of hardener per 1oz of resin. I started with that, but soon found out it was drying much too quickly, so I backed it out to approx. 13 drops per ounce and never mixed more than 10-12 ounces at a time so I could work with it before it started to harden. The real pain was the amount of layers of glass, very time consuming. This thing front to back took me the better part of 2 weeks to build, you know, an hour here an hour there. Put a layer on, let it dry, repeat. The final filler coat was a challenge to get smooth, I just about wore out my orbital sander and went through tons of discs (sand paper). It's kinda rough in spots, sorta like a rock . . lol. The sides that weren't showing when installed got less attention if you know what I mean

Oh, and this was a 5-1/2" top mount depth speaker Polk Audio db104. So 5-1/2" can be done with glass if you don't mind
"adjusting" your seat pan.

Maybe I can get a decent sounding clip if I use my digital camcorder. If so, will post.

And thanks for the compliments guys, it was definitely a time consuming project.

It could use another filler coat and then sanded again. I was just running out of patience and left it go. It's not too bad looking, and the texture helps, but it's not show quality. Maybe someday when I don't have so many other projects going on around the house I'll pull it out and finish it better. But for now I'm happy, it's in the back, under the seat, I never see it really so who knows. Plus the paint is kinda sporadic but that was sorta what I was going for, kinda rustic, like a rock or stone.

I haven't had my 10 year old boy back there to try and bounce his 80lb butt up and down that should be fun.

I just spent some more time adjusting on my system again and all I can say is I'm impressed with this sub more than I can actually express, still. For a 10" this thing hits incredibly hard and clean. Can you say "mirror vibration"? My rear view mirror is unusable at higher volume levels, it's vibrating so much that you can't make anything out, no lie. For the record, I took the door speakers down to a high pass of 100hz, and took the sub up to 140hz, which gave me some overlap that my ears said it needed. My mid bass is more alive now. I'm sure that isn't the last adjustment I'll make as I listen more to different kinds of music and explore the volume level. I'm thoroughly impressed with this sub.

Here's the bad boy powering everything (Alpine PDX-5, 5 channel amp, 75 watts x 4 doors + 300 watts for the sub = 600 watts total RMS):


Here's the carnage involved in installation/hook-up of the amp:



Here's a video of the mirror shake, all from one Polk Audio 10"!!
More than enough bass for an "audiophile" such as myself, total bottom end fill, finally. I'm not trying to shake the neighbors house, I just want all frequencies adequately represented, period. Believe me when I say even the video doesn't show how bad the mirror shakes. Obviously the sound is attenuated in this video like I said earlier, but let the vibrations tell the story!!

Now that's a sub enclosure that looks like it belongs in that truck! Glad the sound is all that you expected as well.
FWIW, I have " bit of experience using glass. If you ever do it again (or for anyone else) here are a few suggestions that may save time/grief:

1) Work with small batch's of resin to keep rushing and waste to a minimum. Mix the reesin for 3 min (min) and then pour it into a flat dish vs cup. It takes longer to kick if it's spread out.

2) If your not good with counting drops of hardner or need to work in closed spaces, consider (marine) epoxy resins. They generally mix 2:1 (read more forgiving) and arn't as stinky/flamable. They do cost more though.

3) Finer cloths take corners/shapes better and give better surface finish's than thicker cloths/matts but take more layers to gain thickness. I like to put on dry cloth then wet it out with a brush and squeege. Wrinkles and folds can be cut and drips should be squeeged out asap. The weave should be wet but not flowing/drenched . Otherwise, the cloth wants to float. To get your final finish, roll/brush, squeege additional resin onto the cloth to fill the weave and smooth it all out.

4) If you make your mock-up out of hard foam, you can shave and sand it to perfection, then lay the wetted cloth right over the saran wrap covered "plug". ( Carfull here, poly resins often eat foam. Epoxy's don't. try a sample first.) Latter, after several coats of cloth, you can carve out the foam and flood the inside of the shell with Acitone to remove/disolve the rest.

hth

WeeHooker said:

Now that's a sub enclosure that looks like it belongs in that truck! Glad the sound is all that you expected as well.
FWIW, I have " bit of experience using glass. If you ever do it again (or for anyone else) here are a few suggestions that may save time/grief:

1) Work with small batch's of resin to keep rushing and waste to a minimum. Mix the reesin for 3 min (min) and then pour it into a flat dish vs cup. It takes longer to kick if it's spread out.

2) If your not good with counting drops of hardner or need to work in closed spaces, consider (marine) epoxy resins. They generally mix 2:1 (read more forgiving) and arn't as stinky/flamable. They do cost more though.

3) Finer cloths take corners/shapes better and give better surface finish's than thicker cloths/matts but take more layers to gain thickness. I like to put on dry cloth then wet it out with a brush and squeege. Wrinkles and folds can be cut and drips should be squeeged out asap. The weave should be wet but not flowing/drenched . Otherwise, the cloth wants to float. To get your final finish, roll/brush, squeege additional resin onto the cloth to fill the weave and smooth it all out.

4) If you make your mock-up out of hard foam, you can shave and sand it to perfection, then lay the wetted cloth right over the saran wrap covered "plug". ( Carfull here, poly resins often eat foam. Epoxy's don't. try a sample first.) Latter, after several coats of cloth, you can carve out the foam and flood the inside of the shell with Acitone to remove/disolve the rest.

hth

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Now you tell me . . . .lol.
Seriously, it had been since high school since I last played with fiberglass and that was ah, some 20 years ago. So this was in all reality kinda new to me again and had to relearn what I was doing again to be proficient.

Everything WeeHooker said is spot on and I'll add just a few more things.

1) I did use two thickness' of mat. Thin stuff for the first few layers to get the general shape and follow the curves better and then thicker stuff for the last few to build it up quicker and make it stronger.

2) Use as small of pieces of mat as is practical and overlap as you go. Most of the pieces I used were about 4x4 or 6x6 maximum.

3) From what I have read, fiberglass is as strong as MDF at 1/3 the thickness. In other words, 1/4" of glass should equal the strength of 3/4" MDF.

4) Air pockets/bubbles are your enemy, they take away from the strength because they are not solid. When ever a layer dried and I discovered any pockets (like on the corners where it wrapped around a radius) I ground them out with my dremel and filled them with resin during the next layer application.

5) Fiberglass should be done in a VERY well ventilated area, this stuff REALLY stinks.

6) Have lots of latex gloves around and be sure to buy acetone for clean up. Acetone can also be used as a thinner in the resin mix. If your resin mix starts to harden in your mixing container before you're done applying just add some acetone.

Well, I finally got some breathing room from projects around this house. The way that enclosure ended up finished was bothering me, alot. Since I know it works awesome I decided to go back over it with a few more layers of filler and sand it out right to give it the finish it deserves. Like I stated earlier I was running out of time and patience last weekend and knew I probably wouldn't be happy with it looking the way it did (my wife calls me "anal", go figure). I also bought paint color matched to the plastics in the truck, so when complete it should look just like another part of the interior. First coat of filler is drying right now. Sand, filler, sand, filler, sand, filler, sand . . my poor orbital sander, I hope it makes it through some more of this . Anyway, I'll get it finished either later today or early tomorrow. In either case I'll take detailed pictures of it since it will finally be looking good and I'll post 'em up for you all.

nismo2point0 said:

Todd, that looks freakin sweet man. Looks just like my MTX thunderform and cost a lot less haha!! great job again and i hope you're happy with the way it turned out, heck I'm happy!

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Speaking of cost, I'm surprised no one has asked me that yet.
I estimate I have about $75 in the enclosure alone, and spent $60 on the Polk delivered. So that's $135 in materials alone. Now add in my $1,379.52 in labor and whew, that's one expensive sub . . .heh.

So anyway, for about $135 and some elbow grease I'll have what I want.

Thanks again for the compliments, that helps make it all worth it.