How To Make A Speaker Enclosure

Well I have written up a little how to for building up a fiberglass box....

How to build your own fiberglass box.

First off measure out the space you have to install the box, it is better to measure twice and build once.  There are 2 different ways you can build the bottom of the box.  If you want to make it conform with the contours of the car then you will need to lay out plastic to protect the interior from resin and then hand lay 3 layers of resin and fiberglass mat to the plastic.  Let it cure before removing it from the car.  The other way is to use wood for a flat bottom, 3/4 “ MDF is a good choice.

Second you will have to cut out rings to mount the subs into.  Make those out of MDF as well and sand them smooth.

Next mount the rings in a fashion that you want.  The more curves you have the more sanding you are going to have to do, so keep that in mind.  For mounting the rings I used 2” strips of wood to make legs and then glued and screwed it all in place.

Next take a fabric that stretches both ways to cover the whole thing ( I used a nylon material ) and staple it in place ( I used a staple gun ).  Mix up some resin and brush it on and let it cure.

Once it is cured well, start cutting fiberglass matting into roughly 6” by 6” pieces and cover the box with the matting and resin.  Do this about 7-10 times to build up a good thickness and make sure you let it cure between coats and sand down any high spots when needed to help keep the box fairly smooth.  When you are on the 2nd or 3rd coat you can cut out the areas where the subs will mount where as there will be no need to build up the fiberglass where you won’t need it.  Once you get the glass built up enough, then move on to the next step.

Now you take a fiberglass reinforced body filler and cover the entire box.  This makes it easier to sand smooth, especially if you plan on painting the box.  Once you get that sanded fairly smooth move on.

For the last coat of material I used a real thin skim of Bondo to make all the curves real smooth.  Try not to use a lot of Bondo.  If the fiberglass reinforced filler was used right then you should not need much Bondo.  Sand it all smooth with 80 grit then working your way to 220 grit to get rid of all gouges in the material.

Now prime out the box with a good sandable primer and then wet sand it with 800 grit to make it real smooth and then you are ready for paint.

The whole job will take a long time, but if you are not in a rush and go slow with it, you can have real good results, and save a lot of money at the same time.  I spent roughly $120 on materials for mine.

If you have any questions, please feel free to ask me, and I will try to answer all of them.

Good luck and happy modding....

How-To courtesy of TF member mustfcs