Problems with fiberglass enclosure

Printed From: the12volt.com
Forum Name: Fiberglass, Fabrication, and Interiors
Forum Discription: Fiberglass Kick Panels, Subwoofer Enclosures, Plexiglas, Fabrics, Materials, Finishes, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=49029
Printed Date: May 23, 2024 at 12:38 AM

Topic: Problems with fiberglass enclosure

Posted By: Gbelous
Subject: Problems with fiberglass enclosure
Date Posted: January 31, 2005 at 11:51 AM

My brother and I worked on a fiberclass enclosure for my car. It is coming out pretty decent considering it's our first time with fiberglass. It is to the point where I have a few layers of fiberglass on it and a couple coats of Bondo. I know it still needs more bondo and then sanded and painted, but the issue now is that it doesn't sound too great. I calculated the correct port, but the entire box itself just vibrates a lot. If I hold it down with my hand the bass sounds much cleaner and deeper.

How can I make it more solid so it doesn't vibrate as much?

I was thinking a few things...add more fiberglass to the inside, add more bondo to the outside, layer sound absorbant material on the inside (Sound-Off) or a combination of everything. Any ideas?

Or could I put some better supports on the inside and secure them to the box?

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Replies:

Posted By: realitycheck
Date Posted: January 31, 2005 at 12:24 PM

You're probably going to have to add more layers to it, I know the bondo is not going to stop the vibration. If you can add more layers to the inside that would be easier on you but its going to be really hard to glass on the inside of the box. If you sanded all the bondo off and then added more glass it will be easier for you in my opinion. If there are any flat parts you can cut out pieces of mdf to match the flat area and glass it to the inside of the box. How many layers did you put on there???

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Learning the trade one fiberglass creation at a time!

Posted By: oonikfraleyoo
Date Posted: January 31, 2005 at 8:03 PM

Not to disrepsect your math skills but unless your a calculus major a ported fiberglass box is extreamly hard to design even if it is thick enough.

Posted By: branvw
Date Posted: February 03, 2005 at 4:43 PM

i agree with oonikfraleyoo, it is almost impossible, I have tried it many times, now i have givin up, i will only do sealed!

Posted By: Alpine Guy
Date Posted: February 03, 2005 at 7:58 PM

Iv managed to do it, but its a pain in the arse, ,the box has to be big, and you have to be able to accuratley measure it with packing peanuts or sand. Then make a slot port, cut a hole in the enclosure, slide it in, then fiberglass it in there.

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2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.