Hi Guys. I went to LOWES today to buy a sheet of MDF, and they didn't have it. The guy showed me a high density fiber board and a particle board. So i bought the 1" particle board, and broke it while i was cutting it.
i want to make an enclosure for 2 subs...can i use the high density or not? also if i do find the MDF, should i get the 1" or 1 and a quarter inch..
thanks

 

3/4" for the mdf is all that's really needed, unless you plan on doing some serious pounding.

do you have a home depot around you?? they have mdf, when i went to lowes i didn't see anything either.

but you might be able to use H-DF, see what other people say.

 

hey vic, i was going to make the box according to the measurements you gave me for my alpine 12" type R's. Yeah i do have a home depot close. I will go there tom.
thanks

 

oh hey. i forgot to say if you can't find any MDF, you could always go with some high quality birch plywood. it is a bit on the expensive side compared to mdf though.

 

The stuff the guy called HDF is probably MDF. Because HDF is about twice as heavy and isn't a normally sought after consumer product. A sheet of MDF is probably 40-50 lbs. HDF is actually better but normally very difficult to find and the mass of the stuff makes it impractical.

 

hi vic. i actually went to LOWES and saw the birch plywood, it was 35 bucks for 1 sheet. Do u think thats reasonable? thanks

 

yeah, that price for birch is reasonable, but you can get mdf for 20 bucks at home depot.

 

ok thanks for the info

 

You could also look into plexiglass, but I heard that costs an arm and a leg

 

i have never worked with it bfr. so i think for now i will keep it simple. perhaps in a few months i will. plus its 2 freaking cold here in indy. and i dont have a heated garage. so if order to work with plexi, i would have to spend the weekend with my rents,,and no way thats happening, at least not for the whole weekend. if i do spend the whole weekend, all my dad and i will do is TEQUILA,,,no sir 2 ,many calories, i dont want to be yelled at by my wrestling coach ,,,,,hmmmmmmm tequila

 

The MDF is the best all around wood for speaker enclosures. The birch is a tiny bit stiffer, but has greater chance of a void in the wood. And a couple small braces eliminate any chance of flexing anyway. The only benefit of plexi is if you want to look through the enclosure. Then you have to be more precise with the volume of the box because you won't want to add polyfill.

But your coach should know that the biggest reason to avoid CH3 - CH2 - OH metabolism. Because during metabolism the bodies abiltity to metabolise fat is disabled. This is the second reason diabetics have to be careful drinking. I mean there are a few calories, 7 per gram, but nothing an active person can't burn off.

 

very true.

 

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But your coach should know that the biggest reason to avoid CH3 - CH2 - OH metabolism. Because during metabolism the bodies abiltity to metabolise fat is disabled. This is the second reason diabetics have to be careful drinking. I mean there are a few calories, 7 per gram, but nothing an active person can't burn off. [/B][/QUOTE]

ok. and why is it that after drinking a lot, the night sleep isn't very good? is it because the body has to work extra to get rid of all that crap, and the poor liver is working extra hard????

 

Alcohol is a diuretic. So if you do not properly rehydrate yourself before sleep or constantly through the night you will be at least moderately dehydrated. As an athlete proper hydration is a priority. Coffee after a night of drinking exacerbates the dehydration because caffeine is also a diuretic. I would start the morning with a large glass of water, some juice, skim milk and a walk or jog/run. About 1 to 1.5 miles per drink.

Sorry everyone for going totally off subject.

 

I have two JL 12w3s and i wanted to make an enclosure that won't be as heavy as using MDF. I was talking to a guy that works at Tweeter and he said to go with light weight MDF wood. he said that lumber yards sell this stuff and that i wouldn't find it at Home Depot. What are your guys take on all this. thanks in advance.

 

i do drink a lot of water bfr bed, but still wake up at least twice to drink more. in the morning i run about 6 miles 5 days a week..thx for the info though

 

i've never heard of light weight mdf. it could possibly exist though. maybe they use a different kind of wood to make it. but i'm not sure on this. that's the drawback from using mdf though, the weight. but in return for using mdf you get no flex, and sturdiness.

if you want something light compared to mdf, why don't you try fiberglassing????

 

how do you fiberglass? Do you mean buy a fiberglass enclosure?

 

what if i used mdf in the back and sides of the box, and did fiberglass in the front? will that mess up the sound??

 

yes, you could do the front in fiberglass, but it'll have to be really strong cause of the weight of the sub. if you are just trying to get looks, do a mdf box, and just add the fiberglass to the front.

yeah, i meant to make a fiberglass enclosure. it's not as hard as it sounds, if you need help just let me know. if you were to buy a fiberglass enclosure it would run you a good amount of money, so i'd just stay away from that unless your loaded.

 

[QUOTE]Originally posted by victor
[B]

yes, you could do the front in fiberglass, but it'll have to be really strong cause of the weight of the sub. if you are just trying to get looks, do a mdf box, and just add the fiberglass to the front.

so build the whole box with mdf, and use fiber glass in the front, on top of the mdf?

 

[QUOTE]Originally posted by dba1999us
[B]yup. that's my plan with my enclosure in my spare tire well. i don't want the top to be plain mdf, so i'm going to do something cool with some fiberglass, same with the amp section of the floor.

 

Thanks, asuming that a fibergalss enclosure and an enclosure made out of MDF with the same dimensions, what would sound better. Or would they both sound the same?

 

I think it is actually birch MDF or something like that. I have seen/used it once. It is significantly lighter. Only a small amount less stiff. It would be an excellent material for fiberglass laminations. A friend who builds custom furniture for a living showed it to me. So most furniture shops may be able to get it. Should be cheaper than MDF because of the lower shipping cost. If you are in VA let me know, I'll check to see if my friend could get a few sheets for distribution to the org.

 

if the fiberglass box is constructed well with good bracing, the two enclosures should sound the same.

 

Another thing to consider is the quality of resin, fabric, and build up. With the MDF there are numerous area's that a novice could make mistakes as well. A glass enclosure can be twice as strong with half the wall thickness. But which will sound better depends on the build quality. And many people would have trouble telling the difference in a blind listening test regardless of build quality.

 

very true. glass is much harder to work with than the mdf, though. with the glass, it's easier to not have a completely sealed enclosure, it you don't lay the layers of fiberglass evenly or don't have bracing you'll get flex.

i think it won't be hard to tell the difference between a decent mdf box and a badly constructed fiberglass box. the installation of audio equipment is the key to a great sounding system, so i have to disagree, and say that it is possible to tell the difference when dealing with build quality.

 

Fiberglass is very strong when used with curves in it, but for a flat panel, it looses much of its stiffness. thats why whenever you see a fiberglass enclosure (lets say in a spare tire well) its usually made out of MDF since its much stiffer than fiberglass......

 

a trick to strengthening fiberglass, is in between layers to lay rope down, so that the fiberglass isn't completely flat.

 

Like any material you have to design around the strengths and weaknesses. The fabric is very strong but you have to keep in mind the orientation of fibers. That's one reason they have tens of fabric styles and thicknesses. I try to wrap in at least two directions and incorporate bracing. I guess the rope is essentially a brace once it is soaked in resin. I generally use wood and aluminum but rope is on my list for a future home satelite enclosure. You can even make a brace out of cardboard. I am kinda favoring pegboard right now as an easily moldable material, that is super absorbent for resin. Once laminated it is more than stiff enough in the direction it is intended to brace. But I use epoxy resin that is magnitudes higher quality than the standard polyester, Bondo resin.

My large flat baffle is mostly MDF because of a few things. Number one is that I had no experience with glass when it was cut. Number two is the ease of inserting threaded inserts. It has a little more work to be done to it but will be made significantly stiffer by composites. For a normal enclosure the MDF alone would be sufficient. But my subs are capable of producing huge amounts of vibrational energy.

 

This past weekend I went to Home Depot in the L.A. area and I was shopping for some MDF to build a floor with in my Max, but when I went to have it cut, the guys there told me that they were prohibited from cutting MDF anymore because of the hazard of the glue used to put the MDF together. It has something to do with cutting it indoors and the particles remaining in the air within the store throughout the day being hazardous to the employee's health over time. I figured that since many of us in the .org use or have used MDF for sound system purposes, you may want to consider where you're cutting your MDF and how often you expose yourself and those around you to it.

This was a public service announcement brought to you by Pit5Bull & Associates...

peace2u

 

i agree, be careful not to breathe in too much dust. any type of woods that are compressed, used chemicals, which aren't too healthy to have in the system. i think they use formeldahyde (spelling might be off. ) in mdf at least. i'm not sure, but i know it's not good to breathe the stuff.

 

I am not 100% sure but think that they stopped using formaldahyde in MDF glue. The stuff that they are prevented from cutting in the store by OSHA is pressure treated lumber. Because that does use formaldahyde as one of the preservatives. But the glue in MDF is dangerous to breathe. Make sure you use a mask and try to keep the room well ventilated. Most good wood shops have a vacuum hose that connects directly to all the cutting tools. That way the air borne wood and glue particles are kept to a minimum. Formaldehyde is also in fiberglass insulation and that's why it's a hazard if left exposed in a room where people may want to breath.

 

thanks for the information jmax, i didn't know that. i always try not to breathe in the dust when i'm cutting wood, regardless of what kind of wood it is. and my mom yells at me when i don't wear any breathing protection.