3.1RS

OK, I am brand new to box making and I would like to know the proceedures to making one. I have the mdf and everything but would like to have a step by step. Including what to seal it with, do i seal the inside or outside and how do i get the speaker wires through to the inside of the box. Anyone with box building experience please post anything you know. Thanks a ton.

SuPeR SpOrT

I just use silicone to seal it, if you want you can seal inside and outside. You need terminals to hookm your subs up to on the inside of the box, unless you want to run speaker wire through your ports. (not recommended it looks sloppy)

AJ_92RS

Liquid Nails. Put it on every seam before you screw the pieces together. After it dries, run a bead of acrylic caulk (not silicone) on all the inside seams.

I've seen a lot of people on here use silicone, and I'm not sure why? It's very susceptible to temperature, and it doesn't stick to wood very well. It expands and contracts and peels itself off the wood.

I work construction in the sheet metal trade. Anytime we put gutters or fascia up (i.e. outdoors) we use acrylic. We only use silicone inside the buildings in a temperature controlled environment.

If you want, just run another bead of Liquid nails on the inside. That's what I do. That stuff is great. Just wear latex gloves when working with it unless you want your fingers coated with it for days.

And I know a lot of people here say "don't bother", but drill pilot holes. Nothing pisses you off more than getting a spit in the wood.

joezero

First off, AJ is completely right on everything.

In terms of a step by step, here goes:

1. Decide on you dimensions. This is a lot harder than it sounds. First off, you will have some exterior dimensions that will limit you. For instance, the rear area is about 41" wide, so you can't make a 54" box. Second, you need to decide what your interior volume will be. The subs will come with a spec sheet that will tell you how much airspace they need. Keep playing with the box dimensions until you get the right airspace. I can help you with that if you need it, but I'm not going to post it unless you need it (cause it's long).

2. Make a build sheet that tells you all the peices you need and their dimensions.

3. Cut out all the peices you need. Measure and measure again. The accuracy of this step depends on your craftsman ship, so if you're bob villa, you've got it made. If not, it may take a few tries to get a cut just right.

4. I like to assemble the box with the more complex side first. This really only applies if you're building a box in the well. Start with the side against the back, because you'll have to indent the box for the hatch mechanism. This way the final peice that goes on is a flat one that goes the entire width of the enclosure.

5. As AJ said, predrill your holes. The glue is what is primarily holding it together, the screws are just for added support and to keep it in shape while the glue dries. Run a bead of glue the entire lenght of the peices to be attatched. Then put in the screws. It's a good idea to countersink the screws a bit. It gives them a better bite on the wood.

6. Before you put on the final few peices that will seal the enclosure, caulk it. I prefer to use the almond colored caulking. It looks nicer and in my opinion is easier to see than the clear. Let it dry before moving on as sometimes small holes develop.

7. Put the back edge on. Caulk it. If you so desire, this is the time to spray a sound deadener.

8. Depending on the size/shape of the top you can cut out the holes for the speakers now, or do it after installation. I've found that with square enclosures, it's easier to cut once it's all assembled. For something like mine (pictured below) it was necessary to cut the top before it was glued to the enclosure.

9. Reach through the speaker hole and caulk the top.

10. If you want to install speaker terminals do so now. What I do is drill a hole slightly larger than the speaker wire I'm using. I run it through and leave enough inside the box to connect the speaker. Then I caulk it on the inside and outside. Just remember if you do this, do it somewhere out of sight. Drill the holes for the speaker screws.

11. If you're covering it with carpet or similar, do so now. If it's a thinner cloth (like I did with mine) the box will need to be smoothed. Use body filler (like bondo) or wood filler to fill any seams, holes (remember those countersunk screws), and majors scratches. Sand smooth. Now apply the covering. I use a spray adhesive to stick it to the MDF.

12. Install the speaker and attatch wire it to the amp.

You're done.

joezero

Here is the one in my car. It'd be a bit much for a first timer, but a simple box for just a pair of subs can be done in a few days.
<img src="https://www.thirdgen.org/techbb2/attachment.php?s=&postid=1175345">

joezero

The finished product:
<img src="https://www.thirdgen.org/techbb2/attachment.php?s=&postid=1159763">

3.1RS

wow this is going to help me out a lot just a couple questions i have 2 12s and they need .9 cubic feet each how do i calculate that when you have so many angles. What are yours and how many cu are yours. Mabye if you have your dimensions i can use yours. I had planed on making one that goes all the way down to the bottom of the well up to the spot where yours meets the back of power hatch. I am worried that will be too many cu. also what kind of calking do you use and what kind of glue? Thanks a ton!



:hail: :hail: :hail: :hail: :hail:

89blackGTA

In our cars that is never the case.

Brian

3.1RS

if there is too much cu in box can i put something in there to reduce the space?

joezero

To answer your last question first:

If (and this hardly ever happens) you have to much airspace, just fill it with whatever the box is made of. You can add additional bracing inside the box or else just stack it up along the bottom.


Here is the part that I have that goes down into the well:
<img src="https://www.thirdgen.org/techbb2/attachment.php?s=&postid=1175342">

I just finished building on for my brother that is even with the latch at the back and slopes down to the ledge behind the back seat. It's 12" high at the back and 6 1/2" at the front. I don't know the exact airspace on it, cause it just had to be bigger than .7 cu. ft.

What type of music will you primarily be listening to? That will have a big effect on the box size. Smaller for rock, bigger for rap. A smaller box will give tighter bass, which is good when you're mostly after just the kick drum. A bigger box is better if you're wanting to bump Ice Cube and have it be heard 5 blocks away.


I can get you the dimensions of the box that goes into the well if you still want it. I made it a little small so that I didn't have any fitment problems. I built the first one to be snug, and even after shaving some off the front and back it still didn't fit. So I took some off the dimensions and built the one in the picture. It fits like a dream.

Those a thread on the board right now called "I need some motivation post pix of your bad azz systems!". You might want to take a look at that to get some ideas for box design.

As far as glue, I just use regular wood glue. When the box is all dried, you should be able to stand on it without a problem.

Once I know what type of music you're gonna be listening to, I can show you how to calculate the dimensions.

3.1RS

I Listen to RAP YO HOMEDOGG..........

joezero

My box is only like .7 cu ft. The min spec for my subs was .65, so I went only slightly over. If your minimum airspace is .9, you'll want at least 1 cu ft, altho probably more.

Here are the dimensions for the well box:
41" wide
11 1/2" deep
The hatch pulldown area is:
17" X 6"
You could go down maybe as far as 4 1/2", I just chose to go a little wider so that I didn't have any trouble at the bottom.
The center section is another 6" down
I made each side 12" wide before it dips down into the well. You can make it significantly less (like 3-4") on the drivers side. But I did it this way so that I would have it be symetrical. It makes it easier to determine where the divider goes.

This means that the only real variable is the height.
Now lets just assume we're going for 1 cu ft. per sub
That means we need 12"x12"x12"=1728"
Now assuming you're making your box out of 3/4" MDF, we need to subtract 1 1/2" from each of our exterior dimensions.
That gives us a width of 39.5" and a depth of 10"
The volume of the area in the bottom of the well is 930"^3
So we use the formula 2(1728)-903/(39.5*10)
We get 2553/395=6.463
So take that roughly 6.5 and add 1.5 for the MDF and you get a height of 8"

You can go to about 12", but that is cutting it extremely close. Remember if you want deep loud bass, the bigger the better. So at 8" the bass may not sound as good as you like. Let me see if I can get a pic of my brother's setup. You might want to try doing something like it, only a little higher in the front.

Your other option would be to fiberglass the well. Altho if this is your first real stereo project, that may be a bit much. You could also extend the enclosure out a little onto the ledge behind the back seats. There are plenty of ways to make it work, it just requires a little imagination some time.

joezero

Here's a pic of my brother's box before it was covered and installed in the car. If you brought up the front end from 6.5" to 8", and stuffed the box with poly fil, you may find you have just enough airspace.

DISTURBthePEACE

Listen to these guys, they know what they're talking about. I just build my first camaro box, and was lucky cuz it fits and sounds awesome. The only thing I would do, and its purely cosmetic, is get speaker terminals...they are the first pic. They look a bit nicer than just drilling a hole in the side of the box and then caulking it shut. Other than that, all I gotta say is GOOD LUCK! . And post pics when you're done. Here are some pics of mine...I did mine a lil different shape...if you want the plans, they're on my cardomain site...click in the sig...

joezero

What gauge wire are you running for the subs?

3.1RS

Im running 4 guage all the way back.