Tweeter pods: step #1

     My goal with this project - customized fiberglass tweeter pods in front pillars.

     I would like to mention that this was my first project with fiberglass, so the result could be better. Training leads to perfection.

     So where to start? As every project - planing is crucial. It is important to know at least basics of car audio setups. Since every tweeter is different not only by dimensions but by sound characteristics, the best way to decide of the tweeter position is by experimenting. To do this you have to get some help. So when your car stereo is running, you have to hold tweeter in one of your hand (other person holds the other tweeter) and try to rotate it, change its location, position, angle etc. This way you can listen and decide in which position the tweeter sounds best. So - there isn't the "correct" position. Only the one you like best.

At this project I was making pods for my brothers car and audio system. He has car stereo with sound processor which is able to create sound delays (to create better sound stage and stereo imaging), so we decided that with the processor in place the best sound from tweeters are when they are at eyesight level pointing to the driver.
      
     Next step is to take off the original front pillar trim. During this project the original trimming won't be damaged, so if you're planning on selling car they can be replaced.

    Every fiberglass project needs some mold (original shape to create replica) on which to create shape of the object. I'll be using the original pillar trim as a mold for the fiberglass. I wrapped the trim with several layers (important, because the chemical reaction of the glue can generate a lot of heat that can damage one layer)  of food film so that the glue and fiberglass wouldn't damage it. Food film actually is very useful because it can adjust to different curves and shapes of the mold.

    So the shape (mold) is ready.

   Next step is to cut the fiberglass cloth into squares (about 4x4 cm). These squares will be used on places that are very curved. If the trim is straight, bigger fiberglass cloth can be applied. Why the different size squares? Because if the trim is curved smaller squares will better apply to the surface without creating bubbles and unnecessary grooves.

    Next - mix the glue. Since polyester resin (glue) consists of two components (glue and hardener) it is very important to mix it in the right proportions. If you'll mix hardener too much - the glue will harden very fast (will be less resistant) and if too less - the glue won't harden at all. So consult the seller to find out the correct proportions (usually it is about 10 %, but NOT always).

   Before doing stuff with glue, I would suggest using surgical hand gloves, because the glue is very sticky and hard to wash off. Also - you MUST do this in well ventilated areas because fumes of the glue are highly toxic.

Additional tip on the gloves - apply a bit of cooking oil on them so the glue wouldn't stick to them as much.

   So the process is as follows - smear the mold (wrapped in a food film) with the glue, then apply first layer of fiberglass cloth/squares, than smear the cloth with glue, so it would be soaked with the glue. After this instantly  apply second layer of fiberglass and again - smear it with glue. Since fiberglass cloth can be bought in different thickness it's hard for me to suggest the number of layers necessary. I used two layers of fiberglass cloth.

   After waiting for a while this is what I got:

   As you can see I left sides as well. Those can be cut off with metal scissors or a small saw.

   After cutting the unnecessary sides off,  the mold can be taken out of the fiberglass shape. After that a bit of sanding and fiberglass shape will have nice curves and edges:

I should mention that while sanding the fiberglass, respirator should be used so that you wouldn't inhale the fiberglass dust that also is very bad for your health. You shouldn't do the sanding while wearing t-shirt and shorts. They don't call it fiberGLASS for nothin'... :)

Updates will follow soon!