DIY - Fiberglass box construction
Learn the basic technique on how-to build a fiberglass enclosure
Install time: about 1 day (painted face add 1-2 days)
Enthusiasts want it all: power, performance and of course stereo. The problem is that a great stereo weighs too much. You could build a fiberglass enclosure but it does not sound as good as wood. Until now.
I realize that the pictures are not for the spare tire are but the steps are the same. This will also work to build kick panel speakers for your front separates or midbass drivers.
Step 1: Determine the purpose, shape and location
For most of us, the logical place for the fiberglass enclosure is the spare tire well. The first thing to do is to tape the area off to prevent any fiberglass or resin from getting on your car body. I highly recommend using 3M Brand tape. Trust me. Other tapes either don't stick or you can remove them. It really makes for an ugly mess.
Step 2: Rough cut TacMat
Now you are probable wondering what does this
product have to do with fiberglass. I
have built many fiberglass enclosure and they had problems. While they were
light, they sounded "pingy" and, well, like fiberglass. Another
problem is that when you mold a fiberglass part into the car, it will creak and
rattle as you go over bumps and rail road tracks etc. That's because your
car flexes and the box doesn't. This is where TacMat comes in. TacMat is
a material made by the Dynamat guys. This material creates a barrier between
the fiberglass and your car that damps the fiberglass (giving you that less
fiberglass sound) and provides a cushion between your fiberglass and your car.
WARNING! Don't try to glass to just any type of foam material. TacMat is one of a small list of foams that will not be destroyed by fiberglass resin. Most will. And the results will be disastrous.
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topStep 3: Form into shape
A real easy step but necessary. Press the TacMat so that it follows the
contours of the floor panel. In the corners, you could use a little double
stick tape or velcro (you do not need too much and too much will present problems
later) You could also cut the TacMat into different pieces and spray glue
the edges together. If you take the later step, make sure to overlap the
seams by about an inch.
Step 4: Make a top wood trim piece
This
step will help you attach a wood baffle face to your
fiberglass bottom. The example is only a 1/4 of an enclosure
so essentially, you would build
a wood ring. Make sure that the wood ring does not contort. It
is important that it remain flat or your top plate will not seal correctly. This
is the simplest way to finish the box. For more custom shapes of the top
plate, this step is not necessary.
TacMat
(a Dynamat Product)
