I own a 2006 Subie Outback, which should tell you a few things:
1. I am a hippie
2. I am politically liberal
3. I care about the outdoors and having fun in it
Only one of the above is true. It's not the first two, which is shocking seeing as how I own a Subaru. To cut to the chase though, I love road tripping and I love doing outdoors stuff, namely snowboarding and camping.
My Outback 2.5i has 60/40 split fold-flat rear seats. This is awesome because it gives me a ton of cargo space. Problem is, I also love music, especially having nice crisp, punchy bass. The stock system is ok, (it's got decent front components), but the bass was lacking.
So I needed some bass, but I also needed to keep my trunk space intact, and that meant no huge box behind the rear seats.
JL Audio makes an awesome Stealthbox, which is custom-made to fit in the little storage hatch cutout on the vehicle's right rear flank just behind the wheel well. Their box is VERY nice, to the tune of $750.
So I used theirs as a guideline of sorts to create my own Stealthbox on a budget.
Because of the odd angles of the cutout, it was clear that the back of the box would have to be fiberglass, which I had never worked with before.
I read lots of great posts online about working with fiberglass. Here's the process I went through, and some pictures.
1. Mask out entire area that you'll be molding. Use masking tape or painters tape.
2. Cover the rest of the car with sheets or drop clothes. (Plastic will work OK, but fiberglass resin could eat through it if you drip enough of it).
3. Use a Sharpie to line out the area you're going to fiberglass. I used some cardboard templates to come up with a basic shape first too. I determined that the face and top and end would be made of 3/4" MDF and the rest would be fiberglass.
4. The space of the compartment area was nearly ideal for a 10" subwoofer (1.5 cubic feet). Make sure you think about math a little bit when doing any project like this because you want ideal performance when it's all done.
5. Buy some resin and fiberglass cloth at Home Depot or Lowes or some hardware store. You can get other (better quality?) stuff direct from suppliers if you live in a large city, but it's usually more expensive.
6. Do one last test fit with your cardboard template and make sure you've thought everything through because once you mix the resin with the catalyst IT'S ON! You've only got so much time before it sets up.
7. TIP: Pre-cut or pre-tear the fiberglass cloth into strips of varying sizes, because once you've got the resin all over your hands, things are going to get sticky. Having a helper might be a good idea too, but it's not completely necessary.
8. Mix the resin per the instructions. Use a plastic bucket to keep the stuff in. USE LATEX GLOVES!! You don't want this stuff on your hands. Also, you're gonna need several pairs throughout the process.
9. Start layering in the strips. There are varying methods of getting the resin on the strips, whether it's painting on or dipping the strips in the bucket then placing them in the mold area. Either way works in my opinion. I used a paintbrush and my hands to smear the resin where it needed to go.
10. PATIENCE.....you'll have to do at leat 5 layers for a decent sub box. It all depends on how powerful your sub is (i.e. how much pressure it will be putting on the walls of the box).
11. Once you're done with the layers, attach the MDF portion (the front half with the speaker cutout) to the still-wet fiberglass. This will allow the MDF to bond to the rest of the box. MDF is porous and will soak up the resin pretty well. Add layers on the inside edges as best you can to help create a bond between the wood and the fiberglass.
-Time for a 4-5 hour break- (to let it set up).
12. Pop the mold. Easier said than done. Some things I read say to grease the area with WD40 before you put the layers in. I did not do this so it was very hard to pull the mold out. Fiberglass is very strong, so don't worry about breaking it. Keep pulling and tugging from different angles until you work it loose and it will eventually pop out.
13. Sand and Fill. Use fiberglass filler (it's a grey sort of paste that you can also get at Home Depot) to fill any cracks or irregularities. Let it dry then sand away, making sure all the edges and joints are as smooth as possible.
14. Create anchor point. I cut a hole 1" in diameter in the back of the box to match up with a pre-existing screw point on the Subie's body. Using a bolt (which I had to custom cut) and some washers, you can create an airtight anchor for the box. This is important to hold the box in place when you are pounding down dirt roads, etc. I also drilled a small hole in the edge of the box for the wiring.
15. Carpet time! I found some cheap black carpet at Wal-Mart of all places. I think it was $8. Coat the contact surface of the box and the carpet with a thin layer of glue and then start fastening down edges. Carpeting is sort of an art that I haven't perfected, but I recommend starting with a large piece, layin the box face down on it, and then making incisions at the curve points. Do all the cutting and strategic thinking before you start gluing, because that stuff sets up pretty quick too.
16. Run wiring through the small hole, then to make sure box is airtight, add some caulking to the hole from the interior.
17. Hook up wires to subwoofer, install sub, and enjoy!
See pics for details. If anyone has any questions about the process, let me know!
