building up strength fast?
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=22146
Printed Date: June 09, 2024 at 9:53 AM
Topic: building up strength fast?
Posted By: pureRF
Subject: building up strength fast?
Date Posted: November 30, 2003 at 8:11 PM
I have a box that is pretty much all done. Its primed and wetsanded i just need about one more coat of primer. Its gonna hold an Eclipse 15 Aluminum running at 500 and i had second thoughts about the strength. Im sure its strong enough but I want to be TOTALLY sure to where i can just crank it to its peak and not have to worry about breaking a box i put hours and hours into and not to mention a ton of money. They hole is big enough to work inside and layer glass. Is there any secret to build extra strength besides just layering mat? thanks a ton
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dream it, build it, fiberglass it
Replies:
Posted By: Steven Kephart
Date Posted: November 30, 2003 at 10:01 PM
How thick did you make it? I usually go about 4 layers of 1.5 oz mat and have never had a problem. And this includes a sub in a .36 cubic foot sealed enclosure and powered by 1200 watts.
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Posted By: Velocity Motors
Date Posted: December 01, 2003 at 10:53 AM
Making the enclosure about 3/8" thick with braces should be sufficient. I went to 5/8 " on my (3) Boston Acoustics 12.5 LF enclosure ( SEALED ) and it sounded solid.
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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA
Posted By: pureRF
Date Posted: December 01, 2003 at 1:36 PM
Velocity I have never put braces, how do you suggest i do this because there are 2 part where it is molded to the floor then to the back of a seat that are flat and i think bracing would be a good idea there. They are thick but i just wanna make sure.
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dream it, build it, fiberglass it
Posted By: Velocity Motors
Date Posted: December 01, 2003 at 2:31 PM
The bracing has to be done in the building stage ( before combining the top to the enclosure ). This adds structural rigidity to the enclosure from the inside. The only other option is for you to use a resin expander for high build projects. This will add thickness and strength really fast.
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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA
Posted By: pureRF
Date Posted: December 01, 2003 at 7:32 PM
Where would i find resin expander?
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dream it, build it, fiberglass it
Posted By: iaudio
Date Posted: December 01, 2003 at 8:09 PM
UScomposites has it. Look for cabosil.
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Posted By: pureRF
Date Posted: December 01, 2003 at 8:37 PM
Do you mix this in with resin and just spread it on? or do you use the resin with expander in it on mat?
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dream it, build it, fiberglass it
Posted By: iaudio
Date Posted: December 08, 2003 at 10:47 AM
You can use the resin/cabosil mix with matting or cloth. Don't use to much or it will negatively affect layup.
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Posted By: no ka oi
Date Posted: December 09, 2003 at 2:52 PM
depending on how much extra glass and resin and time you have, you could build a test box. To make the test box, make it exactly like what you want the real one to be like, but make it super thin. This sounds kinda weird, but if you build it to break it, then you know where the weak spots are. Just built it with maybe two layers of glass, put the sub in and crank it up 'till it breaks. This will show you where you need to add more glass. Engineers do this with race bikes and car hoods and other such things. Just make it super thin, use it 'till it breaks, then reinforce the place where it broke on the real box. This way you will know where it breaks on future boxes because you have tested it.
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if you dont know how to fix it right, just fake it
Posted By: pureRF
Date Posted: December 09, 2003 at 4:09 PM
Sounds like a good idea but i def dont have time
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dream it, build it, fiberglass it
Posted By: pjon
Date Posted: December 09, 2003 at 5:13 PM
yea, that sounds like alot of work for that
Posted By: cmaroman95
Date Posted: January 09, 2004 at 6:21 PM
what you could do is go ahead and put the sub in and not crank it up all the way. then as you turn up the sub watch the box. if it starts to flex and move then you might want to think about adding the expander. and when i say flex i don't mean a little vibration i mean swelling to twice the origianal size.
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"get in where you fit in"
Posted By: pureRF
Date Posted: January 10, 2004 at 4:32 PM
Tahnks for all the advice everyone but the box is done now. I didnt add any glass but when i drilled thru it for a wire to go into it it was 1/2 inch thick. I guess i was just paranoid.
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dream it, build it, fiberglass it
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