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ckunke002
12-13-2013, 07:59 PM
About to build my first ported box, finally have all the details worked out how I want them and am ready to jump into it. One last thing I'm concerned/curious about is bracing inside the port itself, connecting the port to the exterior wall it's a couple inches from.

For example, if I am running a slot ported box with the slot on the left side, do I need to somehow brace the port lengths to the left and rear walls (which make up the other side of the port)? Or just try to brace the port lengths spanning across the box to the right wall and front baffle?

Thanks for any wisdom shared!

thatguy12
12-13-2013, 09:11 PM
how much power are you running. i have never braced.the slot port itself. but i haven't had a over 1500 rms sub set up. i always do a double baffle no matter what, also the port itself helps add structurial integrity to the box itself. if you have a beast setup a little extra bracing cant hurt.

ckunke002
12-14-2013, 05:39 AM
how much power are you running. i have never braced.the slot port itself. but i haven't had a over 1500 rms sub set up. i always do a double baffle no matter what, also the port itself helps add structurial integrity to the box itself. if you have a beast setup a little extra bracing cant hurt.

I will be running about 1.2k max. I plan entirely on running bracing in other areas that I can, but bracing inside the port was something I was very unsure on. Thanks for answering!

T3mpest
12-14-2013, 10:00 PM
No need to brace inside the port. What is the length of your longest panel no being braced by the port?

ckunke002
12-15-2013, 01:16 AM
No need to brace inside the port. What is the length of your longest panel no being braced by the port?

This is what I have in mind right now... was thinking of running a couple lengths of maybe 2 inch wide strips of 3/4" mdf from baffle to rear wall and rear port length, and from right wall to the first port length. If that makes sense to you.

With that long of a width should i run just 1 mdf strip from second port length to rear wall? Seems like a far span to have nothing on there

Also was wondering about if there is much significance concerning sub placement on the front baffle. Like if it would be better on the far right or far left or around the middle or something else...

http://i223.photobucket.com/albums/dd215/ckunke002/ScreenShot2013-12-14at100414PM_zps193b8358.png (http://s223.photobucket.com/user/ckunke002/media/ScreenShot2013-12-14at100414PM_zps193b8358.png.html)

ckunke002
12-15-2013, 01:18 AM
And also with sub displacement and braces the internal volume would likely drop to something like 2.2 if not lower.. should I over-compensate for this more than I currently am?

T3mpest
12-15-2013, 12:37 PM
And also with sub displacement and braces the internal volume would likely drop to something like 2.2 if not lower.. should I over-compensate for this more than I currently am?

That box isn't very big and likely won't need much bracing. I'd double baffle and flush mount the front and possibly the back as well and probably call it a day on that. You don't have a huge box here nor are you running huge power. Double baffling should add enough strength in this case on your large panels, while being much easier to execute.

ckunke002
12-15-2013, 05:20 PM
That box isn't very big and likely won't need much bracing. I'd double baffle and flush mount the front and possibly the back as well and probably call it a day on that. You don't have a huge box here nor are you running huge power. Double baffling should add enough strength in this case on your large panels, while being much easier to execute.

This is something else I was wondering about... How would flush mounting be a good idea, or a better idea than surface mounting on top of both boards? Aside from cosmetic purposes, there goes all the extra strength right?

And you said that back as well.. you meant simply doubling up on the back right?

ckunke002
12-15-2013, 05:22 PM
And since i haven't done this yet maybe there's something I'm missing, but what exactly makes running a couple braces hard to do? I figured i would just take a couple spare pieces of mdf maybe 1.5 or 2 inches wide and cut them to length and glue into box.

T3mpest
12-15-2013, 09:26 PM
This is something else I was wondering about... How would flush mounting be a good idea, or a better idea than surface mounting on top of both boards? Aside from cosmetic purposes, there goes all the extra strength right?

And you said that back as well.. you meant simply doubling up on the back right?

You won't lose any strength by flush mounting. The extra baffle isn't really to hold the subs weight. It's to reduce panel flex. The 2 panels overlap everwhere except for the 3/4 inch. So now it's trying to flex 2 panels instead of one. You can't flex only one panel when they are glued together. Think of trying to rip paper, it's very easy to rip a single sheet, as you add sheets it gets well more than 2x as hard as you double sheets. A panel that is double baffled is around 4x stronger than a single baffle and still 2x as strong as a single panel of the same weight, so 2 .75 is better than 1 1.25 thickness. Flush mounting gives you all the strength of a ugly double baffle, along with better aesthetics. Topping it off, flush mounting is usually louder on the meter since it creates a smoother baffle surface.

And yes, if your worried about your back panel, just double it over as well. There is nothing hard about bracing, but your eating up air space and reducing smooth airflow unnecessarily. I have nothing against bracing, when it's needed.. A 2.5 cubic foot box for a single 12 just doesn't really need it. For bracing to be effective, it needs to be near the center of the panel. You can't get it near the center on the rear wall without throwing it into the port. The front side, is your other next longest side and the sub will likely go there. A window brace could be used horizontally, but then it's bracing your shortest walls, they don't need it. Double baffle the front and back, maybe some 45's in your corners if you want to get frisky. It'll help airflow and very slightly brace. Corner bracing isn't as effective though.

ckunke002
12-16-2013, 01:38 AM
Cool, thanks for all that advice! Since i do not own a tablesaw, if i were to buy some 2x2s at lowes or home depot, would they be able to make 45's for me you think?

Slo_Ride
12-16-2013, 01:41 AM
if i were to buy some 2x2s at lowes or home depot, would they be able to make 45's for me you think?

nope

Side Show
12-16-2013, 01:44 AM
^^ lol ask em dude, we don't work there lol

ckunke002
12-16-2013, 02:28 AM
lol... is there any other way besides with a table saw...?

Slo_Ride
12-16-2013, 11:55 AM
circular saw, jig saw, scroll saw, hand saw, butter knife. well maybe not the last one.

ckunke002
12-16-2013, 03:36 PM
just seemed like getting an accurate 45 degree cut on a small piece would likely end in losing a few fingers with most of those options. Lol

mlstrass
12-17-2013, 02:57 AM
If you needed to brace the port walls I would do 1 1/2" hardwood dowels, but at that power level I highly doubt you need it...