The stock location for the JBL Sub is way too small for any decent sub. I am installing a Rockford Fosgate P3D2 sub that needs 1.0 Cubic Feet of Airspace to breathe. There just is not enough space without stealing the existing spot for the JBL, but I didn't want to buy a JBL panel and modify it. So I decided to build a custom box out of fiberglass and MDF and pray that online tutorials in fiberglass would give me a clue.

1. DO NOT BUY FIBERGLASS AT HOME DEPOT / LOWES / WALMART. The stuff sucks. Go to a boating place like West Marine. The bondo brand crap never set up and we had to start all over.

2. Do not use painters blue tape. It does not stick well enough. Again, this taught us a brutal lesson in lost time. Go with the next grade up from painter's tape.

So those lessons learned, next lesson was we rebuilt the mold out of the good sticky stuff and covered up the electrical outlet / cigarette lighter outlet with tape. What we did not do and now know TO DO is cover the tape with a thin coat of carnuba wax, then hairspray the wax. The wax acts as a release agent and the hairspray coats it and lets the epoxy stick. So your mold releases right off. We started doing this midway through after we almost broke the first try at the glass job simply trying to get it out of the mold.

Then we started laying down the glass. We used a two part epoxy from West Marine combined with fiberglass tape. It is way stronger than the "mat" that they sell, but takes more coats. Takes about 15-30 minutes between coats to get tacky when you can apply another coat. We did four coats then removed. Here is the first coat.

These are three shots of the fiberglass after it has been removed. We sanded, trimmed the edges, and prepared the mold to fit into the opening. It obviously got dark so we called it for the night. This is what we have for the main section of the mold and we have to work on the rest of the back of the box, but we are cutting MDF to make the top, sides, and front. You want to use as much MDF as possible because it is sturdy, holds its shape, and is flat.

More images to come this week. Just super stoked because this is the first time I have ever glassed anything. My dad worked on boats in SF many years ago and it is a father-son-grandson project.

http://imgur.com/a/ydnc8/all

Looking good! Can't wait to see the finished product!

I've been wanting to make two fiberglass sub boxes for a while, but alas work, weather, and SO not having a car until recently have hindered my efforts.

Looks great can't wait to see what it looks like. It's also interesting to see you're an imgurian as well.

I work from home. If not for imgur and reddit, I would actually get something done in life.

Would you make any for members on here after yours is complete?

Not hard to make but a lot of lessons learned. I am not sure I would want to do it again.

More photos are on imgur now.

Attached Images

   

I have to fiberglass the MDF to the other fiberglass, cut the top MDF piece, and seal the box. When that is complete, I can install the sub. Trying to get the box built completely then I will take the front off, cut the hole, and install the sub.

I built up two plates underneath the box to attach it to. I have to carpet those as well. Then carpet the whole thing.

Hi N5G,

You do EXCELLENT work bro, "lovin' the ingenuity and commitment"! Now tell me... when you're done with your fiber-glass sub... "Can you make me a 10 cuft box so I can put these over the wheel well"(?) ...I have nowhere to put my lunch pail on my way to work now... hahaha!



"Keep up the good work brother"!

I am not sure I would want to do it again.

Where’s the finished product??

Yeah we have been waiting 4 years to see it hahahaha

Awesome stuff. Any idea how man cubic feet of airspace you have there? Looks fairly large!

I like this, thinking of doing it to mine!!