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plazman
10-10-2004, 01:33 PM
Im building a box for a 15 XXX

i heard some peeps talking about bracing the box...

how do i exactly brace? Do i need some kind of support to the hold the thing? Sub is kinda Heavy..

Double the front?

Please Advise. Thanks

avs20
10-10-2004, 05:01 PM
Here's how my box is braced...
http://home.comcast.net/~avs20/Box/box3.JPG
http://home.comcast.net/~avs20/Box/box4.JPG
http://home.comcast.net/~avs20/Box/box5.JPG

Hope this helps!

plazman
10-10-2004, 06:34 PM
thanks... thats perfect.

also... would 2.5-3 cubes ported be too small for a 15xxx?

really cant go any bigger and im kinda stuck with this 15. will i be ok?

OLD_SCHOOL
10-11-2004, 05:16 PM
realy shoudl be 4 to 4.5 cubes ported

Moe Lester
10-11-2004, 05:41 PM
That bracing is gonna cause some db loss. just a few triangle type braces is probably all you really need.

someone16
10-11-2004, 06:33 PM
**** thats a big port moe

plazman
10-11-2004, 06:42 PM
someone said in another thread that i will loose alot of low notes and the sub will become very punchy.

would these affects cause the sub to sound horrible ?



can bracing be in the outside ?

plazman
12-05-2004, 11:40 PM
That bracing is gonna cause some db loss. just a few triangle type braces is probably all you really need.

got pics ? what do they look like?

Moe Lester
12-05-2004, 11:43 PM
Heh, been a while lol

Honestly, you dont need much bracing for a daily box... look in the sub cutout, youll see what i mean. those triangles are 4" squares cut diagonally.

http://img9.exs.cx/img9/5535/x9obox8.jpg

plazman
12-06-2004, 06:50 PM
thanks
any specific part of the box where they should be placed?

Nikuk
12-06-2004, 06:55 PM
in the middle of longer walls.

plazman
12-06-2004, 07:01 PM
how many pieces for a 4 cube box?

InhumanAcura
12-06-2004, 07:03 PM
Dont waste your time...

plazman
12-06-2004, 07:04 PM
Dont waste your time...

why? no bracing needed?

InhumanAcura
12-06-2004, 07:07 PM
why? no bracing needed?

If you could stand and jump on a 4^3' box and make it flex Id be surprised...

plazman
12-06-2004, 07:11 PM
so your saying by standing and jumping on the box, does it stress the box more than a sub? sub like 15 xxx

brandontw
12-06-2004, 07:12 PM
you should be suprised then,inhuman, i had a 4 cube ported box for my 2-12's, and it got some pretty good flex on, 3/4 inch mdf, and it was dual chamber!, yes i used lots of glue and screws, it just flexed

brandontw
12-06-2004, 07:14 PM
and sub flex isnt the same as standing on your box.

plazman
12-06-2004, 07:14 PM
**** i hate getting mixed reviews.

brandontw
12-06-2004, 07:15 PM
some bracing sure wouldent hurt, but it also wouldent hurt to bad not to, dont stress about it

Moe Lester
12-06-2004, 07:15 PM
well, RE MT 15" and a ~4.5 cube box w/ 2kw didnt flex hardly at all... no bracing.

plazman
12-06-2004, 07:18 PM
conclusion: some of you guys received the crap batch of MDF at your local lumber yard.

brandontw
12-06-2004, 07:19 PM
hmmmm... maybe i just **** at building boxes, but i dont see how.

Moe Lester
12-06-2004, 07:20 PM
my box in my sig doesnt flex, its got no bracing in it either. its 5 cubes

brandontw
12-06-2004, 07:21 PM
strange.

plazman
12-06-2004, 07:57 PM
i must also say that my box is fiberglass with mdf bottom

InhumanAcura
12-06-2004, 08:01 PM
i must also say that my box is fiberglass with mdf bottom

This is something you should have mentioned earlier....It would make it easier if you had a pic..

brandontw
12-06-2004, 08:04 PM
yeah, id like to see this

plazman
12-06-2004, 08:16 PM
no pic now, but it just a regular box with 30 bottom width 14 height 14.5 depth, top width 36

i could of used mdf, but i wont be able to come up with 4 cubes.

plazman
12-06-2004, 08:36 PM
pic

Moe Lester
12-06-2004, 08:38 PM
those flat f/g surfaces arent going to be very strong. Its probably best to lose the airspace and build it out of MDF the right way..

plazman
12-06-2004, 08:45 PM
i still have to add more layers on it..

i wasnt sure of the measurements so i kind guess my way though.

this is my 3rd box. first one was out of MDF, that didnt fit, 2nd birch plywood, that didnt fit.

kinda late to change anything.. i'll make sure it doesnt fly.

my trunk so d a m n small and i went this stupid big woofer (15xxx) should have gone with jl 12 w7 and everything would have been simple.

InhumanAcura
12-06-2004, 08:49 PM
For future referance, use as much MDF as possible and f/g the rest.

Have you tried building in the trunk...I cant fit a 2.5^3 box throught the trunk opening, but Im running 7.5^3's...

plazman
12-06-2004, 08:53 PM
i could have built it in the trunk, but i wont be able to access my spare. i really cant take the chance without the spare, im riding on 19" rims, and with the roads around here... trouble could happen anytime.

in the future... i dont think i'll ever touch something like this again. way too much work. next car will have a custom fiberglass trunk done by a professional.

do u think i'll be fine as long as i layer my glass right?

brandontw
12-06-2004, 08:54 PM
hmmmm

plazman
12-06-2004, 09:12 PM
hmmmm


good or bad?

kungfoojesus
01-11-2005, 05:01 PM
I tried the same thing, trust me that FG is gonna flex. Go back and build as much of it as possible out of MDF and try to only use FG if its a rounded edge or something. Stay away from huge flat walls made out of FG. They flex no matter what! That's a lesson I've learned from experience.

g30ffr3y
01-11-2005, 05:08 PM
how does one actually build a box IN a trunk???

InhumanAcura
01-11-2005, 05:13 PM
how does one actually build a box IN a trunk???

Put it together out of the trunk w/o glue and then disassemble it. Make sure not to build it to where you wont have access to the screws/nails....

Then put it together inside of the trunk, lol..Ive done it with the last 4 boxes in my car.

g30ffr3y
01-11-2005, 05:15 PM
but dont you NEED some screws on the bottom and stuff? or
on the sides where the box would be too tight to the trunk to
get a screwdriver in there???

could you show me a pic of a box built in a trunk???

thanks.

InhumanAcura
01-11-2005, 05:49 PM
Dont build it to where you have to screw the pieces together from the bottom. I fully assembled as much outside as possible cause of the mold then put the rest together inside the trunk. It had a few angles that go from 24"s to 36.75"s wide from the rear to the front baffle and from 13.5"s to 16.25"s tall front rear to the front...
http://memimage.cardomain.net/member_images/11/web/635000-635999/635350_99_full.jpg
http://memimage.cardomain.net/member_images/11/web/635000-635999/635350_103_full.jpg
http://memimage.cardomain.net/member_images/11/web/635000-635999/635350_122_full.jpg

I just ripped the front baffle off this morning to make way for 2 15's, gonna be fun fitting 2 15.5" subs on a 36.75" baffle and still have ~80-100^2"s of port...