View Full Version : enclosure stuffing and bracing

12-07-2012, 11:23 AM
1/ i might have some closed foam left over, can i use that to line the inside of a box properly?
2/ what exactly can i pick up at home depot to line the box?
3/ when bracing the box, can i just use an L bracket/"hinge".
4/ due to the size of the box, i cannot brace from the inside, because i cant drill the pilot holes, is it ok to brace on the outside with the L bracket?

12-07-2012, 11:51 AM
1. closed cell foam removed air space so no
2. nothing
3. no
4. no

12-08-2012, 08:42 AM
Thank you, but would anyone like to provide a little more detail to the answers.

1/ I made the enclosure a little larger than spec so taking up air space shouldn't be a problem. Besides the closed cell foam is about 3mm thick and will be glued to the walls, so I don't really see that hampering air space. Just curious if it is as good as stuff like polyfill in helping with reonance.
3/ Why? Isn't it about structural integrity? And a "L" brace will do that. So why isn't it good?
4/ Again, why? Are you saying If I cant brace from inside it doesnt make sense? Besides, bracing from the outside with "L" brace should provide more structural integrity, so what am I missing?.....Besides the default of "this is how it's done".


12-08-2012, 08:51 AM
How much larger is the box than spec?
What type of box? ported or sealed?
Which and how many subs will be installed?
What's the thickness of the material used to make the box?

12-08-2012, 11:02 AM
specs call for 7.5x11x11, i made it 9x11x11 or 13(leaning toward 11 11)
one 10"
3/4 mdf

12-08-2012, 11:22 AM
Just use a peice of wood equivelent to the diffference in volume and secure it inside. In terms of structual integrity if you have glued then screw or nail the sides together properly then there is no need to do anything else.

12-08-2012, 11:23 AM
That small of a sealed box should not need bracing.

12-12-2012, 10:05 AM
oh oh, i drilled one of the screws in a bit too far and the head caused it to split horizontally about 1" at the corner of the outer baffel holding the sub. i drenched the crack with wood glue with wishful thinking. is it a lost cause? will it eventually fail? any way to repair or salvage this?

12-12-2012, 02:12 PM
Just wood glue and clamp it, it will be fine. How much power are you putting on this sub? What material did you use to make the box and what thickness?

12-12-2012, 02:52 PM
350w rms, 10". prob wont even run it more than 250w rms. i used 3/4 mdf, elmer carpenter glue max and 1 1/2 #8 (http://www.caraudio.com/forums/usertag.php?do=list&action=hash&hash=8) screws. Although, when i sealed the lid i ran out of the glue and ended up mixing the elmers with titebond premium wood glue.

12-13-2012, 10:23 AM
yes you do want stuffing, but not foam of any kind. at the hardware store get some of the Ultra Touch insulation (recycled denim). experiment with fill levels (50% to 100%).

bracing corners isn't as important as bracing the panels. for that, i use a 1x1 or 3/4" dowel rod to secure both sides and top/bottom. i agree that small enclosures don't require the same bracing as large boxes.

12-14-2012, 12:25 AM
Well, I already put the close cell foam in, about 2mm thick and covering 50% of each wall...a bit too late. Soooo, tell me why exactly I should take it out now? Because I really cant see any detriment to it being in there, and actually see more benefit in that it will absorb the highs, help prevent the resonance, and not take up the space that stuffing would to prevent air flow. So why please?

Also, about to do the final step of carpeting, I'm ordering 3m 90, and Professional Speaker Box Carpet - RTBoxes Subwoofer Enclosures (http://www.rtboxes.com/fabric-speaker-box-carpet/) (hoping the edges are perfectly straight).
1. Do I glue the carpet down first and then cut the around the hole and terminals?
2. Do I cut the hole exactly the size of the hole so I have the lip of the speaker on top of the carpet? Or do I cut the hole big enought so the lip of the speaker only makes direct contact with the wood?
3. The lip of the speaker has a good solid feeling rubber around it, do I still need to put foam or something between the speaker lip and box? (kind of seems unnecessary)
4. After I glue the carpet down, should I secure it with any staples?
5. I think I'm going to use industrial strength velcro to secure it in the trunk (remember the size), any thoughts?
6. Any other suggestions, please feel free.

12-14-2012, 01:13 AM
I'm not too sure about the closed cell foam you glued to the inside of the box, seems more like it won't do anything but shouldn't hurt.

as long as you glued and screwed all the edges well on the box you shouldn't need bracing on a box that small on that little power.

I would just carpet the whole box up and then cut the holes out. Overlap the carpet under the lip of the sub right up to the edge of the hole in the wood.

Don't use staples unless you have to.

Velcro should work fine for a box of that size and weight.

Pictures of your work and the box would help also, if you took any while building.

Good luck.