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View Full Version : 1/2 mdf vs 3/4



samger2
06-12-2008, 02:26 PM
What are the negatives with using 1/2 inch vs 5/8? I'm limited on space and trying to maximize my volume plus all I can find at the local hardware store is 1/2 and 3/4...and I'd really prefer not to use 3/4, once again so I can maximize my cuft...thanks!

Thrillho
06-12-2008, 02:53 PM
Negatives to 1/2" would be that it is more likely to flex under pressure. However if you brace the box internally and don't plan on using a sub that is too heavy or powerful you could probably get away with using 1/2". You should probably double up on the front baffle if you do go with 1/2".

jdc753
06-12-2008, 02:57 PM
Any chance of using fiberglass? If your this limited on space that you are considering thinner materials than fiberglass may be your ticket. It really isn't that hard to use either, just read up some things on here and other places and you should be good to go. Only downside would be if your enclosure has many large flat surfaces (this is the weak point of fiberglass.) Also how big of a woofer(s) are you planning on running in this enclosure and with how much power? A single lower powered sub would be able to work ok in a box made from less than 3/4" material. One more thing, working with 1/2 is a bit trickier than 3/4 at least to get screws in and such can be much harder.

samger2
06-12-2008, 03:13 PM
Well I'm working with rockford P3 slimline subs...two 10's...I basically need to make it as slim as possible...and it's pretty much just a rectangle box.

Ed Lester
06-12-2008, 03:18 PM
I wouldnt suggest using any thinner than 3/4" for MDF. If you want thinner use a solid Birch or fiberglass.

jdc753
06-12-2008, 03:27 PM
Do you have extra room to gain volume by expanding the height or width of the box to maximize how thin it is? If you look at the manual on the kicker CVT they actually show how to cut out behind the speaker and put a metal plate across the outside of the box behind the sub to gain just that little bit more. You could try something similar to this, but I would recommend looking into some fiberglass and going that way, if you can build a box out of MDF you can build one out of fiberglass too

samger2
06-12-2008, 03:50 PM
Well...yes, I do have room to expand the width and the height. Honestly, I don't really have any interest in messing with fiberglass again. I agree the finished product is fantastic, but the expense and the mess and the time is more than I'm ready to get involved with again. I don't want to be laying fiberglass and getting it on me in 95 degree heat...plus I've only done a couple glass boxes, the first was a complete bomb and the second was decent...but pretty much a lesson learned.

Then comes the bondo and sanding.

So in other words...I'd much rather just build it out of mdf...for my purposes it'll be much quicker and much easier and if I can get my numbers down just right it should be just as sufficient.

skmfkr
06-12-2008, 03:52 PM
maybe use 1/2" all around but use 3/4" for the front baffle. or like someone else said double the front. but i dont see any reason for a 1" baffle. but it would probly be cheaper than buying two diff sheets

hemi=22s
06-12-2008, 03:55 PM
p3 slimlines prob dont even weigh 20 lbs each but might want baffle a lil thicker than 1/2

wu501
06-12-2008, 03:56 PM
just go with the 3/4". A sheet of 1/2" mdf has a lot of flex compared to a sheet of 3/4".

Mr Cabinetry
06-12-2008, 04:38 PM
I've built plenty of enclosure's with 1/2" MDF and with no complaints what so ever.

And for what power those subs can handle rms given the xmax they have, 1/2" MDF will hold up just fine with the addition of bracing to it.

Cbass
06-13-2008, 02:48 AM
5/8 mdf is the minimun i would use... i think that 2 p3's on a 1/2 mdf box will make it flex a lot... go with 5/8 minimum... IMO

Louisiana_CRX
06-13-2008, 02:55 AM
1/2 well braced and wrapped in a layer of fiberglass...would probally work

samger2
06-13-2008, 09:32 AM
ok then...next question. Anyone know where I can get 5/8 mdf? None of the Lowes and Home Depot around here have it...

Mr Cabinetry
06-13-2008, 09:56 AM
ok then...next question. Anyone know where I can get 5/8 mdf? None of the Lowes and Home Depot around here have it...

HD or Lowes may be able to order in the material for you, but, you might pay thru the nose for it. Try local lumber supply company's, they may stock it though I highly doubt so.

He!!, do this. Build the entire enclosure with 1/4" MDF and shoot it with a few coats of Duraliner, the d@mn enclosure will be indestructible or put a few layer of FG over it.

PV Audio
06-13-2008, 11:29 AM
People seem to underestimate .5" MDF. It holds up just fine, and it's my go to material for small home audio enclosures. The problem is that in the end, you usually end up having to use as much space as 3/4", because you need to brace it more heavily. That's really hte only problem besides it's harder to screw into .5" than .75".

Mr Cabinetry
06-13-2008, 12:14 PM
People seem to underestimate .5" MDF. It holds up just fine, and it's my go to material for small home audio enclosures. The problem is that in the end, you usually end up having to use as much space as 3/4", because you need to brace it more heavily. That's really hte only problem besides it's harder to screw into .5" than .75".

I would agree to the extent that using 1/2" mdf would required some bracing, but not to the extent that it would displace so much that it would be like just using 3/4" MDF and no benefit was gained at all.

For the types of bracing I use for enclosure's the amount of total displacement is no greater than .10 cu.ft., but, to my credit I use 3/8" or 1/2" MDF for those bracing elements as well as for making slot ports.

He!!, that ranger box i designed and will be building is entirely 3/8" MDF, but , I know that it ain't going to come apart.

samger2
06-13-2008, 01:53 PM
I haven't built very many boxes...but I've never braced any of the boxes I've done. What is included or required to brace a box?

PV Audio
06-13-2008, 08:18 PM
I haven't built very many boxes...but I've never braced any of the boxes I've done. What is included or required to brace a box?All that bracing is is coupling the enclosure's panels together so that vibrations are reduced. Look in Mr. Cabinetry's sig for pics of his boxes' interiors, as he's the preeminent king of bracing on the forum. :)