Building a Custom Sub Enclosure


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Hey guys n gals,
I'm new here and have been searching awhile for a DIY on creating a custom sub enclosure and haven't had any luck. I read a bunch of tutorials on fiberglassing and figured id give it a shot so im gonna post what im doing each day for the next couple of days in case it helps anybody.

First off, what I wanted to do was build a box to house 2 10" subs that looked like it belonged in the trunk. I decided not to go with side panel boxes because of the look im trying to achieve, but anyone wanting to go that route the method would be identical.

Supplies needed: ( It may turn out you need a couple additional items
as this is a work in progress and its only day 1)
1 Masking tape
2 Fiberglass Mat
3 Fiberglass Resin
4 Aluminum Foil
5 MDF Board 3/4" preferably but 1/2" would prob work for 10s
6 Some stretchy fleece like material
8 Bondo
9 Sandpaper
10 Some type of finishing material (I plan to paint my finished enclosure
but you could also carpet it )
11 Rubber Gloves
12 Face Mask
13 Paint Brushes (I'd get several cheap ones from the Dollar store as you will throw these away)
Thats all i can think of right now I'll update this list if i use anything else

Lets get started.

I started off by masking off the part of the trunk i wanted the enclosure to fit in ( you could probably frame a lot of this out of wood and it would be faster but i couldnt find a local store that sold MDF board so i decided to make it all fiberglass, plus it should fit perfect when its done)


Next I covered the trunk in aluminum foil. This is to help the fiberglass form come out and also to help protect your interior. Resin is extremely messy you do not want to get this on your carpet. Although i didn't do it I would suggest putting down some plastic over the rest of your trunk to make sure you dont get it anywhere else. I dont know how much this will help at this point but before i started laying down the fiberglass i sprayed the aluminum foil down with pam to help it come off later.


After thats done you just mix your Resin and hardener ( these should come together and mixing instructions will be on the can) and layer on your fiberglass and paint it with the resin. Be sure to work in small batches especially if its warm out as the resin will dry fast. My can said i would have about 12 mins of working time but it was more like 5. I mixed about 8oz of resin at a time. Also this is the step you'll need the mask and gloves for, as I said resin is very messy and puts off very strong fumes.


The resin I was using said it takes about an hour and a half to cure but it was hard to the touch in about 15 minutes. I built up about 2 layers of fiberglass and resin to make the structure solid enough to remove where it will be easier to work on. After I was satisfied I had enough fiberglass on I left it to cure for and hour and then I removed it from the trunk.

Thats all I got done today before it started getting dark. Tomorrow I'm hoping to reinforce it with a couple more layers of fiberglass, build the rings for the speakers and get started on the front of the enclosure. This should move along much faster now that I dont have to be laying in the trunk of my car to work.

Any questions feel free to ask but remember this is pretty much an experiment to me at the moment too. I'll update this daily as I get more done and hopefully be finished by this weekend as thats when my vacation is over.



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