A Very Basic
Fiberglass Enclosure "How-To"
Disclaimer:
This "how-to" page was put together with the intent that the reader will have
some basic knowledge of woodwork, box building in general, and basically... is
not an idiot!
Please read through the entire process first, as I may have left some of the basic materials out of the list. You will need to fill in the gaps and adapt this process to your specific needs. As stated above, this is a BASIC how-to.
Materials needed:
1 Gallon of resin (w/ hardener)
One package of Fiberglass Matting
A good body filler (not Bondo) and spreader
(i.e. Rage Gold by EuroSoft is my choice)
A few yards of a medium thickness stretchy fabric (fleece
or box carpet works great!)
3M Spray Adhesive
Household Aluminum Foil / Tin Foil
Scissors and/or Utility knife
Cheap Cheap Cheap paintbrushes (The Dollar Store)
Rubber or plastic gloves come in handy too! (Work clothes
too)
3/4" MDF and basic woodworking tools for building a frame (saw,
drill, etc.) (router if possible)
Staples and Staple gun
Sand Paper ranging from 60grit up to 600grit
*A well ventilated area to work in*
Possibly a few other materials I may have forgotten
If you think of any, please email me and let me know
A general note: I will refer to "fiberglass" often, but use it as a general term indicating any fabric that has been molded and hardened using a resin mixture. The material may or may not necessarily be actual fiberglass matting.
Let's Begin!
First, we start off by cleaning the area we want to work in. In my case, I was making the fiberglass enclosure mold directly to fit the front half of my spare tire wheel well. The process will be the same for making it fit the entire wheel well, just adjust your plans as necessary. I applied a few good coats of Plasti-Kote Spray In Truck Bed liner, mainly to act as a good sound deadener, and relieve some of the metal rattles commonly heard in vehicles with loud stereos. This is a spray in material that is easy to apply, and can be found at many local stores in the $5 - $7 price range. It comes in different colors, I chose red for obvious reasons. Before applying, make sure the surface has been scuffed with 80grit sand paper thoroughly cleaned.
Here is the hatch and wheel well after it has been coated with
the sound deadener:
I drew black lines with a marker indicating the area that I wanted my enclosure to come to. I then made a frame out of 3/4" MDF. My front and rear piece are solid wood, while the sides will consist of fiberglass. It is possible to make strictly a frame, and have all sides be comprised of fiberglass if you so choose. The #1 reason I chose to use wood for the front/back, is that my box will be ported through the back, and the wood was easier for that reason. As for the front, I will have my cross-overs mounted there, and did not want to mount those directly to fiberglass for fear of it cracking while screwing them to it.
My subs will be flush mounted, hence the need for the double layered trim rings for mounting the subs. I cut out the circles slightly larger than needed, and the wooden rings will give me a good solid surface to mount my speakers too. I then created "stilts" for the rings to sit on so I could get a good idea of the angles that the rings would be at
As you can see in the above pictures, I "rabbitted" the edges, or "notched"
them. I took roughly 1/4" deep, by approximately 1/2" into the the board.
This is for when we stretch the fabric, so it lays flush with the top surface.
This is where your router comes in handy. As you can see in the picture, I
also roughed up the edges quite a bit so the resin can attach a little better.
For a better idea of "rabbitting" or "notching", see the below diagram
You'll learn later on why this 'notching' is an important step
I did the final angling & securing while the box was in the hatch so I could get a good mental visual picture of how the subs would look when it was all finished.
in the above pic, you can see my mounting stilts on three sides where the trim
rings were fastened to the frame
Below, you can see how the frame looked before I started to stretch the fabric over the edges. I unscrewed the rings for the next few steps after I was sure that they were just the way I liked them!
After the frame was all ready and the sound deadener spray was dry, I lined the hatch area with tinfoil. I then placed the framework inside the hatch in the desired position. I chose to use box carpeting for the bottom of the mold. I used spray adhesive and formed the carpeting to the contour of the wheel well, and over the edges of the frame as you can see below. I then saturated it with resin. Once it was tacky, I applied fiberglass matting to the entire mold as well to give it some more strength & thickness
You want to make sure that all layers are good and saturated, giving your project a uniformed thickness and strength. It is much easier to work with the fiberglass matting if it it cut up into smaller squares. I cut mine approx 3" x 8". Smaller or larger work just fine. See what size you're comfortable with, and go at it.
By laying in the tinfoil, I am able to simply "pop" the entire mold right out of the wheel well once it is dry.
Once the mold was dry, I took it out of the car. I then
placed the speaker trim rings into place.
Go to PAGE 2 to see this