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SPL140.2
12-17-2006, 08:56 PM
im still a noob at fiberglassing, how many layers do i have to put down to make an enclosure very, very rigid??? itll be going over a cardboard base.

crazy4ozs
12-17-2006, 09:05 PM
until you can stand on it...so id say 5-6

crazy4ozs
12-17-2006, 09:06 PM
or i guess 7-9 if you going by the poll

SPL140.2
12-18-2006, 08:44 AM
going over 7 is that overkill??

CBFryman2
12-18-2006, 08:47 AM
Depends entirely on the enclosure, On curved areas you dont need as much, on flatter areas you need more layres.

THe best tests are standing on the area and pushing as hard as you can with your thumb. Pushing as hard as you can with your thumb and standing on it will both put more pressure on it than your stereo system ever could so if it doesnt flex you are good.

SPL140.2
12-18-2006, 08:48 AM
yes it will be a circular "tube" enclosure

rollerdj
12-18-2006, 08:53 AM
what size / type sub are you putting in there. some cheap 10'' sub isn't going to be nearly as strong as a, lets say, a 15" RE XXX. the bigger and nastyer the sub, the more layers you would wanna put on. i would say if it's not going to have any flat spots in it, 7 or 8 would be just fine.

PowerNaudio
12-18-2006, 09:20 AM
like stated above you have to test the panel by applying pressure to it, in order to know if the panel is strong enough. i would start with 7 layers, then test the strength and add mare layers accordingly and if necessary. a way to make the enclosure stronger is to add bracing to the enclosure, in a fiberglass enclosure i have found that its comfortable to use 1/2" polyester rope which conforms to the curved faces of the panels and makes for a very strong brace that can be resined in place.

SPL140.2
12-18-2006, 10:06 AM
what size / type sub are you putting in there. some cheap 10'' sub isn't going to be nearly as strong as a, lets say, a 15" RE XXX. the bigger and nastyer the sub, the more layers you would wanna put on. i would say if it's not going to have any flat spots in it, 7 or 8 would be just fine.

10" HD3

SPL140.2
12-19-2006, 02:14 AM
going over 7 is that overkill?? I think im just gonna do 10-12 layers to be on the safe side :D

ramos
12-19-2006, 09:20 AM
What weight mat ? Makes a huge difference. 5 layers of 5oz is a lot weaker than 5 layers of 15oz biaxial :)

CBFryman2
12-19-2006, 10:35 AM
What weight mat ? Makes a huge difference. 5 layers of 5oz is a lot weaker than 5 layers of 15oz biaxial :)

x2

Though he is probably using 5-6oz stuff from Home Depot.

Also, Move to cloth. Two layres of cloth with the weaves at 90* from each other is stronger than two layres of mat when the two are the same weight.

Cloth has directional strength, mat sacrafices directional strength to be stronger in all directions but you can criss cross cloth to gain back the strength in any direction.

ramos
12-19-2006, 10:53 AM
x2

Though he is probably using 5-6oz stuff from Home Depot.

Also, Move to cloth. Two layres of cloth with the weaves at 90* from each other is stronger than two layres of mat when the two are the same weight.

Cloth has directional strength, mat sacrafices directional strength to be stronger in all directions but you can criss cross cloth to gain back the strength in any direction.


Not necessarily. Usually the reason one is chosen over the other is that cloth conforms better to curvy surfaces , where as mat tends to be harder to lay on the curvy surfaces . Changing the bias with each layer of mat will yield just as strong a final product . Mat builds thickness a lot quicker than cloth as well . :)

CBFryman2
12-19-2006, 12:09 PM
I stand corrected. :)

SPL140.2
12-19-2006, 01:09 PM
pics of the cloth??, i do have mat from home depot

ramos
12-19-2006, 03:53 PM
Cloth is the woven stuff :)

http://www.fiberglasssite.com/catalog/10%20oz%20fiberglasssite%20++++.jpg


http://www.fiberglasssite.com/servlet/StoreFront

SPL140.2
12-20-2006, 03:56 AM
thank you :D

CBFryman2
12-20-2006, 08:49 AM
Cloth is the woven stuff :)

http://www.fiberglasssite.com/catalog/10%20oz%20fiberglasssite%20++++.jpg


http://www.fiberglasssite.com/servlet/StoreFront

That's some pretty heavy cloth. :naughty:

Wouldnt need but two layres on a surf board. Less glassing more fun. :yumyum:

nVRuckus
12-20-2006, 09:00 AM
yeah the weight of the mat will determin how thick to make it. I wold actually use a mat/weave combination myself. it is about 22oz and 3-4 layers of that is pretty good though the thicker you go the better is your doing SPL.

ramos
12-20-2006, 09:02 AM
I tend to use 15-17oz. Biaxial stitched mats for sub enclosure reinforcement . Three layers and you can park a buick on it :)

rollerdj
12-20-2006, 09:19 AM
has anybody bought off of this fiberglassite place before. is the product and service any good?

ramos
12-20-2006, 09:39 AM
Buy from Mike all the time . Bulk prices are good . And shipping is pretty fast :)

rollerdj
12-20-2006, 09:44 AM
cool, thanks. i'll have to give em a call later. all the places round here charge a arm and a leg.

SPL140.2
12-20-2006, 02:27 PM
thanks for the info nv ill pm you after work.

SPL140.2
12-21-2006, 01:20 AM
so basically the heavier the mat the less layers you have to lay down?? Im still gonna do about 9-11 layers cause i want it as strong as can be.

ramos
12-21-2006, 06:46 AM
Pretty much. As long as you switch the bias with every successive layer and work out air bubbles, you can use what you want. The enclosure is gonna need to be the same thickness to prevent flexing , and resonating regardless of mat weight. Just the heavier weight stuff takes a lot less layers to achieve it. Won't be much savings in resin, as heavier mat will soak up more resin than the lighter weight stuff. I usually don't count the layers myself . I don't care how many it takes me to achieve the stiffness I want . As long as I get it right :)

SPL140.2
12-21-2006, 09:31 AM
its pretty interesting on the poll the opinions are pretty scattered, so from what i can tell from the poll everyone does it different lol