12" Fiberglass Sub enclosure build thread

[ハチロク]

Originally Posted by niceguy21

If the fiberglass fleece cured already and have already added a good amount of fiberglass layers underneath the fleece, you can use an orbital sander and try to sand it flat as you can, then use body filler to fill in any pores and imperfections. Once done shoot some primer, sand at 800 to have as flat finish for paint. Shoot paint coats and then cleat coat and should be ready to go.

the fleece is cured already but I don't have any actual fiberglass on it yet. just one layer of resin to keep the fleece in place. Did you put fiberglass on the inside of the enclosure? did you have to work through the speaker hole? That couldn't have been easy...

[wheelhaus]

Originally Posted by ハチロク

the fleece is cured already but I don't have any actual fiberglass on it yet. just one layer of resin to keep the fleece in place. Did you put fiberglass on the inside of the enclosure? did you have to work through the speaker hole? That couldn't have been easy...

If you think about it, the first layer is only there to hold a shape. So, you can grind and shape it however you like before/while you add thickness. If you burn through some small areas trying to smooth it out, you can lay some glass to patch over it. If its a larger area, you might need to stretch another piece of fleece. Once you're happy with the shape you can sand down any rough/sharp protrusions. Later in the process once it's built up thicker with glass, you can smooth it out even more, just be cautious to not get too crazy with material removal. You'll be able to see each layer as you grind it away as an indicator of how deep you're going.

If the wrinkles are in an area where it already overlaps the main shell, just sand/grind it away. The fleece doesn't need much overlap on the shell, even 1/2" is plenty to hold the shape until more glass is wrapped around it.

Instead of bondo, you can make a paste with resin and microballoons as a thickener. Using this instead of bondo to smooth the outer wrinkles will create a stronger bond than having a layer of brittle bondo in between layers of glass. Mix it quickly (so it doesn't kick too early) until it has a consistency like frosting.

If you want to add strength inside the enclosure, you can use this thickened resin like caulk around the inside corners where the fleece meets the shell. This isn't quite as strong as fabric, but the microballoons add structure to the resin, and you can smear it around blindly into the corners without having to see everything. Use a mirror on a stick to see what's going on in there. I recommend starting at the farthest, hardest to reach area first, and working toward your opening. (Again this isn't necessary but can help add some strength).

[ハチロク]

I finished fiberglassing and did a test fit in the car. It fits like a glove and I think it looks pretty good. Next step is body filler and sanding, then more body filler and more sanding and so on and so on...

Let me know what you think!

[IBill4You]

Looks great! When can you build mine? Lol

[labskaus]

poor Woofer ... with some holes in it. You need a Grill

[ハチロク]

Originally Posted by labskaus

poor Woofer ... with some holes in it. You need a Grill

they're not holes. Just dents. and it was free lol can't argue with free.

[Fender0122]

Looks good! I've been wanting to do this in my audi for years.

[wheelhaus]

Looks great so far!

[ハチロク]

I went a little crazy with the bondo but it looks really smooth now. I'm pretty happy with this for now. The fit is perfect. I was worried layers of fiberglass and bondo might make it not fit quite as well but it still fits.

Here are a couple pictures of the build so far. This is mostly stuff I finished over the weekend but haven't gotten a chance to upload the progress yet. I just ordered some carpeting to cover it but I have to wait for that in the mail so I am sort of stuck for now. My plan is to start working on some wiring and maybe look into plans for an amp.







as you can see from this picture I left the back a bit unfinished but hopefully none of that will show so it won't be a problem. I still put a layer of bondoglass in some of the weak looking areas on the back, that's why its a different color. I also knocked down some of the high spots so at least it slides smoothly.



I do also need to think about a terminal cup. I might have shot myself in the foot by not taking it into consideration earlier but I hope there is a flat enough spot to put one that won't require too much fabrication. I'm thinking I will probably put it on the back in that flat spot towards the right hand side.

Let me know what you think!

[Shankenstein]

Great work! Fitting a 12 in our trunk is a challenge, and everything is coming out looking professional.

There's no shame in Bondo. You could paint or vinyl it with that smooth of a finish.

Thanks for taking the time to post it up.

[ハチロク]

I'm almost done!!!
here are a couple of pictures of my progress so far. I am working on wiring and installing an amp now and hopefully I'll be able to post the final build after the weekend.

[niceguy21]

Originally Posted by ハチロク

I'm almost done!!!
here are a couple of pictures of my progress so far. I am working on wiring and installing an amp now and hopefully I'll be able to post the final build after the weekend.

Nice!!! Came out pretty clean. Props to ya!