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hazardous0388
04-06-2008, 01:08 AM
I myself have made a bracing thread before but here is my concern. Is there any added benefit in putting bracing along the sides of the box, all 6 sides, without putting any bracing from top to bottom or left to right, having only the ends of the brace touch the wood? just curious on why some people decide to only use bracing on the sides...

thanks in advance
Dustin

:D:D

hoxie08
04-06-2008, 01:14 AM
maybe if its a ported box and you have bracing through it it might cause noise???

hazardous0388
04-06-2008, 01:21 AM
so what stops the flex of the box if theres no middle supports? just enough bracing throughout the sides and a double baffle?

djman37
04-06-2008, 01:32 AM
Brace for any area larger than 1 sq ft. All axis need bracing; X, Y and Z.
'Window frame' bracing is one way. It works well since it should match your side piece measurement already. It doesn't require any more tools that you've already used for the initial box contstruction. Cut either sqares or circles to make panes that leave the structural integrity of the axis intact. This also gets two of the three axis.
Triangles from the sides can help, 4" wide brace pieces can add strength to long spans.
Other methods work too, large dowels, and triple thick MDF pieces can be used.
All-thread and such methods require you to cut through what you are trying to make stronger.
I'm not a fan of the double baffle because of the weight to strength ratio.

my .02 Good luck.

when you tap on the box with your knuckles, it should sound like concrete with a very high resonance, not low and boomy. Tap on a well constructed home speaker and see what it sounds like.

hazardous0388
04-06-2008, 01:55 AM
but how does window frame bracing stop box flex?

mlstrass
04-06-2008, 09:08 AM
window bracing normally ties the top/bottom/sides together. I use that whenever I can, but not also box designs have room for it...

djman37
04-06-2008, 09:56 AM
but how does window frame bracing stop box flex?

it braces the X and Z axis as well as top, bottom, front vertical and back vertical! If you follow through with the Y axis window pieces(2 because they have to be split to fit the XZ one), it's a pretty sturdy box.

Immacomputer
04-06-2008, 01:46 PM
but how does window frame bracing stop box flex?

It helps because when an enclosure tries to flex, the panels are either trying to move in or out but each panel tries to move the same direction. If the panels are trying to flex in opposite directions (each both flexing either in or out) with something attached between them, they will counter each other out. It's basic physics at work.

If you just put bracing on one panel at a time and doubling it like a double baffle, then you're really just mass loading it and raising the resonance point. If you put the normal to the panel surface, then you create a panel as thick for .75" as the bracing panel is long (creating a T shape inside the enclosure). That form of bracing makes the panel very strong at that point and splits the flexing into the planes to the right and left of the brace. To get an idea of its effectiveness, think about watching a jump rope oscillate up and down. Then imaging somebody holding the jump rope right in the middle. From there, you would have two smaller jump rope oscillating sections but they wouldn't move up and down as far as it did when it was the entire rope. That's basically what happens in that kind of bracing.

When it comes to a daily setup, bracing won't make a huge audible difference and may hurt or help on a meter but the variance will be pretty small. I brave to ensure the longevity of the life of the enclosure. A well braced enclosure will not have much panel vibrations and that means that the joints go through less stress which means then enclosure will last longer.

That's just how I view it.

deentownmac
04-06-2008, 03:56 PM
so what stops the flex of the box if theres no middle supports? just enough bracing throughout the sides and a double baffle?

I don't think you are actually wanting to know about window frame bracing, as it is different from the bracing that you were describing in your opening post. The bracing you were asking about, is like this? http://i44.photobucket.com/albums/f47/300GTE/brace.jpg

I was wondering about front to back flex as well as side to side flex.

boltpride
04-06-2008, 04:25 PM
http://i37.photobucket.com/albums/e93/ripmacdre1/bracing.jpg
No flexage in this box. lol. Courtesy of guy on my myspace who i do not know. :)
http://i37.photobucket.com/albums/e93/ripmacdre1/bracing2.jpg

deentownmac
04-06-2008, 04:32 PM
http://i37.photobucket.com/albums/e93/ripmacdre1/bracing.jpg
No flexage in this box. lol. Courtesy of guy on my myspace who i do not know. :)
http://i37.photobucket.com/albums/e93/ripmacdre1/bracing2.jpg

This is window bracing.