Granted, I'm no expert, but I would say: Get to sanding!
Ok so here goes. I'm trying to make twin FG sub enclosures in the back of my 2001 daewoo lanos (don't laugh!) to house a pair of reverse mounted Audiobahn 12" subs. its my 1st attempt at fibreglassing the problem that i have at the moment is as follows:
I put the 1st layer of fibreglass matting in with no problems at all, as in all smooth with no bubbles etc, however when i added the second layer in (still working in the boot as the glass would not be anywhere near strong enough not to warp if i removed it) i ended up with a shed-load of bubbles in it, that i only noticed once it had dried. I want to know if there is a way i can fix this, with out pulling the whole lot out and starting again? any advice on this would be greatly appreciated!
also are there any pitfalls i sould look out for when mounting the speakers the way i want to? man i should research a lot more before i do all this!!!
cheers, AJ<br /><br />
figured the best thing to do would be to rip the lot out and start again - could not be bothered to do all of that sanding!!! - came across a wicked little tool to guard against all of the bubbling problems that i had before - a paddle roller - haven't seen a lot mentioned on the site, but its taken all of the hassle out of the removing of bubbles stage.
my next question is i am failing to see how to do the volume measurements on the install, as the negative i have is only 3 sided..... woes of biulding one in such a pitifully small boot (or trunk). if anyone has some ideas on how to do this that would be very appreciated - i'll whack some pics up of my work in progress soon so you can all critique away!
You're going to have to build up braces with speaker rings to hold the speakers. Once you have the base of your mold in the trunk, you can attach this brace/speaker ring system, and then you can wrap fleece around this to give the curvature you want. Cut out the holes where the rings are, and then sand like crazy and paint
Another trick to get bubbles out is to really keep an eye on it, if you see bubbles forming, take a paintbrush (I'm assuming you're applying with a brush) and just dab the bubbles, they will come out.
a fiberglass roller will work really well, but on a curved surface they may not work 100%, you can get different shaped ones but sometimes it can be difficult.
something else you can try that may help is coating the surface u are applying the glass to with a coat of resin then apply the glass, then work more resin thru from the top. this will ensure that there is resin on the back side, as that what causes alot of the bubbles.
also try chopping ur paint brush down to about 1" long so its alot more stiff and not so much like a paint brush as u want to dab the resin with a stipling motion (?make sense) and try not to paint it on as this wont work it thru the weave,
Are you going to cover the box with anything when you done??
usually people use fiberglass rollers. Also, if you're letting it completely kick before the next layer you're going to end up with bubbles no matter what. This is because the fiber drys in irregular shapes. You cannot lay the fiber back down flat because of this. This is one reason to lay it a few layers at a time and to use a roller where possible. Else, you will always have bubbles to some extent unless you use a rather expensive vacuum tool. This is part of learning to work with glass, learning how to deal with these issues.
btw - thread moved to the fabrication forum.
thanks guys, a lot of useful tips there, it's actually about 99% bubble free, maybe due to the fact i'm using some really heavy matting and working with a small area.
anyway i'll get the pics up and you guys can judge for yourself.
ARGH! new question now! - i really need to know how many layers of 650 mat i need to put in for my negative before i can pop it out of the trunk of my car without warping, and how many it is gonna need to be strong enough to support the vibes from my 500w sub. also any advice on powercaps would be majorly appreciated, as i kinda know i need one, but don't really understand why.
the greatest irony is that the fabrication is the easiest bit! its just making sure i dont mess it up aloong the way! great forum by the way people - more info that the rainman with an encyclopedia...
until the next time
East Coast Audio UK
Daewoo Lanos "Woo of Doom" Show Car
Finish Line - not even in sight!
TOTAL SPENT SO FAR £250
regarding caps - I'd suggest you do a quick search in car audio for 'capacitors' as this subject has been beat into pulp.
As to how thick you need it for a 500watt sub...not that thick for only a 500watt peak power sub. Also, your sub is not a 500watt sub. It's peak power handling might be 500 watts, but you're referring to it in an incorrect manner. When referrign to how much power you have you might want to refer to the amplifier and how much RMS (NOT peak) power it's capable of producing.