Could someone explain all the materials i need to make a box and how what deminsions would I need to get a 1.25 cubic foot volume?

 

Materials:

MDF, 3/4
Drywall nails, 1.5in will work.
Wood glue
Silicone

For size of box, use this box calculator: (rectangular)
http://www.customcarsound.com/calc_box.html

I have another calculator page for triangles/wedges, but the page takes longer to load than that one.

If you need clarification on how to make the box, plz reply what part.. the materials above will make the box solid Just built 3 last weekend .. heh

 

Remember that your sub will take up x ammount of volume inside the box. So, if your sub takes up .25 cubic feet of space, build your box to the dimensions of 1.5 cubic feet. I have used dense particle board (3/4" 0r 5/8", around $12 per sheet at your local hardware store.) and it works just fine. Just remember to cut your panels VERY square and true. Also, remember that the GLUE is what holds a box together, the nails only really hold the box together until the glue sets...thus you need very tight fitting surfaces (glue doesn't bond well unless the surfaces are touching.)

 

Ok, not to diss Autofanatic here, but use screws instead of nails. I have built quite a few boxes in my time and nails just don't work, unless you are gonna use a ton of them and you have a nail gun. He is right about the glue really holding the wood together, but also use some silicone or bathroom caulk to seal the interior seems of the box. This will make the box air tight. Bracing is also a good idea, this keeps the box from flexing too much and losing SPL. Any more questions?? Post here for more help, there are quite a few people around here who know what they are doing. Good luck!!

 

I'm not trying to start a war here, but I too, have built many boxes in my day (along with houses, cabinets, and countless pieces of furniture) and nails have worked beautifully every time. One of the problems I have seen with screws is splitting out the board. If you are not very careful (ie. pilot holes) it is very easy to split out your box, and then you never get good strength in that area. Both screws or nails, when used properly, will work fine. If you decided to use nails, make sure you use FINISH nails. What I also do, is use the scraps from construction (a piece of particle board 3/4" x 3/4" x whatever length the side of the box is) and glue them to the inside corners of the box. Bracing, as DustyRoads described is also highly recommended. I also recommend caulking underneath the lip of the speaker when you screw it into the box, just make sure you use silicon based caulk, or you will have a difficult time removing the sub down the road....

 

It's all good here Autofanatic...you have had success with nails and I have had success with screws. Do you use a nail gun, or do you actually hammer in all the nails individually?? I'm just interested to see what someone else does. You're right about drilling pilot holes for screws and even after you do that, you can still crack the wood, I have had problems with that in the past, but it was just me drilling to close to the edge and tightening down the screws too much. Caulk around the edge of the sub is a great idea too, gives you a nice air tight seal around the woofer and you get get that everytime if you ever have to remove it.

 

Thanks for the info everyone. I think I understand on making a box now im just having some problems figuring out the exact dimensions with all the things that effect it.If it helps the subs im gonna install are 2 12" Infinity Perfects which have a mount depth of 6.50".

 

If you use screws, don't forget to countersink the
the holes. Also, you can get carpet & grill covers from crutchfield and adhesive from home depot. After carpeting, let it sit in the garage for about 1 week else you most likely will get high from the fumes.

good luck.

 

How do I calculate things such as all the screw holes and bracing into the volume?

 

You should account for the bracing when it comes to the volume of the enclosure, especially if you are going to use a lot of bracing. The screw holes will not make any difference to the overall volume of the box though. Do you have a manual from the subs?? Usually in the manual it will list a volume that is recommended for the sub, that is a good starting number.

 

Go to Infinity's website, and they give the dimentions of the box needed to give the desired results. Use those dimentions in some form. they already take into acount the woofer displacement.

 

Errrr... sorry i dunno what i was smokin.

I meant drywall screws. I dont like nails Too easy to screw up.

Definitely countersink & predrill. Less chance of f'n up, and countersinking makes carpetting easier.

 

thanks

 

I hammer the nails in individually. I have used nail guns in the past, but have found that the quicker something is done, the quicker one can screw it up!!

 

Also I coated the whole inside of my box with Plasti Dip, made by Performix. It's a multi-purpose rubber coating for like tools and stuff. It's also a sound deadener. You can get it from Home Depot for like $3-$4. You'll notice the difference right away. I ended up coating my whole trunk with it.

 

yup.. coating the inside of the box with ANYTHING will help keep it airtight and seal off any small cracks in the seams you don't see..

the stuff I use is white "elastomeric roof cement".. it's like a really thick latex paint- water based at that.. covers pretty well, and when it dries (overnight), it has a rubbery texture to it. doesn't smell too bad either.. this stuff is thick enough to cover small gaps and holes.


another good one to use is regular clear polyurethane- like you'd use to finish regular wood after staining.

One more neato trick I've learned.. accidentally drill a screwhole in the wrong spot? those strike-anywhere wood matches work GREAT! just put a drop of wood glue over the hole and us a hammer to tap the match stick into the hole. when it won't go in any farther, just snap it off flush with the surface. when the glue dries, sand it smooth with 100grit paper, and no one will know it was ever there!

 

Matt.. GOT CARPET?