Anyone good at Making sub boxes?

[CSCustomCars]

I was wondering if there's anyone here that can make an MDF sub box, or at least knows how to? I need a crash course. Can't afford to get a pre-fabbed box, so I need to make my own.

I'm gonna get 3/4" MDF if I can at Home depot or something, and know how to make the basic shape, but what do i seal the box with? How do I carpet it? Like, do i glue the carpet on it? What kinda glue do I use?

What's the should I cut the holes with a sawzal?

[CT9A]

You can get 3/4 mdf at lowes, home depot, or menards. You deff don't want to use a sawzal to cut anything for a box, because they are very hard to make acurate. I use a circular saw to make my cuts, but you could use a jig saw. I use either bath tub silicon, or urethane sealant to seal my boxes. It just depends on if I making the box for me or someone else, and how much they are paying me.(bath tub silicon is cheaper) Alot of people use nails to hold their boxes together, but I like using drywall screws. They hold the box together better, and if you drill a pilot hole before you put the screw in the wood wont crack. To cut the holes for the subs I use a jig saw, and a hole saw to cut the holes for the terminal cups. I use 3m fabric adhesive to glue carpet on.

[JonsZX2SR]

Table saw or radial arm saw to make accurate cuts.

Use corner bracing made from leftover MDF or from pine 3/4" stock

Use carpenters glue and big clamps to hold things together. Use an air powered nail gun to shoot 1.5" or 2" brads or staples. Don't use regular nails. A few 1-7/8" or 2" #6 sheet rock screws can also hold the assembly together while the glue is drying. Let the glue set for 24 hours.

Cut the holes using a router with a cutting bit and a template. Quality sabre saw plus a lot of patience is a second choice.

->Circle cutting jigs (http://www.partsexpress.com/webpage.cfm?webpage_id=3&CAT_ID=54&ObjectGroup_ID=876)

->Speaker carpet (http://www.partsexpress.com/webpage.cfm?webpage_id=3&CAT_ID=48&ObjectGroup_ID=826)

Use carpet of linoleum adhesive smeared on the surface to bond acoustic carpet. Tack the couple of end seams with 3/4" staples using the air gun.

-> PartsExpress.Com (http://www.partsexpress.com/)

Examples are shown below for both car and home audio speakers:

http://home.att.net/~wessonj/Images/Dual_8_Sub.jpg

http://home.att.net/~wessonj/Images/Single_8_Sub.jpg

http://home.att.net/~wessonj/Images/ZX2_Spk1.jpg

http://home.att.net/~wessonj/Images/Speaker2.jpg

[CT9A]

Jons way is deff the way you would do it using nails. I would still seal the inside of the box with some type of silicon or another type of sealant to make sure shes good and sealed. I don't use nails because every box I've bought/made a box using nails I've blown it apart, but I also use some very high wattage amps. I deff like your method for the carpet Jon. I'm gonna have to try that on my next box, because the 3m adhesive sometimes doesn't hold.

[JonsZX2SR]

Caulking is optional but will help seal the boxes. Usually the flexible carpet adhesive seals the air leaks.

A few cross braces using round or square bar stock and screws helps as well. The dual 8" box I built for a friend (shown above) had a 1.5" round bar connecting the speaker plate with the reverse face. It was located between the speakers and held in place with glue and a screw at each end.

[CT9A]

You do good work...Id post up some of my boxes but I lost all of the ones I had saved to my computer when it crashed in may.

[CSCustomCars]

Thanks guys. I'm not sure I can make a good enough box myself, so maybe I'll just save up for the pre-fab box that was also made for the subs I have.

Thanks for the write ups though. I'm gonna give that a shot when I get some 10's to add, and I have lots of time.

[Loser47]

a cheaper box shouldnt cost but about $40- i bought the boxes for my 12's for $35 a piece. they are decent boxes, not the best, but they are well sealed and they are massive. I no longer have any room left in my trunk because of them. They are scosche boxes, I got them at sounds great

[SeRiousZX2]

This is how I have been making boxes for about 17 years now. This article was taken from Crutchfiled. I do a couple of things different but overall its a perfect beginners article.

Cost for materials (not including the sub): Around $25

Time spent: Around an hour and a half *
*Remember that the time you spend on this project may vary — it will depend on the complexity of your box's shape, and the tools you have at your disposal.

Tools and materials:
• Jigsaw
• Electric drill with bits for pre-drilling screw holes and driving screws
• 3/4" MDF (medium density fiberboard)
• 2" drywall screws
• Panhead sheet metal screws (1/2" and 3/4")
• Carpenter's glue
• Silicon caulk
• Non-hardening rope caulk
• Speaker terminal cup

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/tools.jpg

1. Choosing your subwoofer.
When choosing a subwoofer, carefully note the manufacturer's recommended enclosure size, especially if you have limited space in your vehicle. The box volume tells you how big your enclosure needs to be for maximum performance from the sub. The box shown in this article was intended for my Honda CR-V, so I wanted to make sure it wouldn't take up too much space. With that requirement in mind, I chose the Alpine SWE-1041 10" sub. The manufacturer recommends a box volume of 0.6 to 1.25 cubic feet.

2. Designing the box.
To determine the correct dimensions for any subwoofer box, you can follow these steps:

1. Determine the minimum depth of your box. Measure the depth of your subwoofer and add 2 inches. This measurement is the minimum depth of your box (in this article, the depth refers to the front-to-back dimension of the box, with the woofer being mounted to the front).
2. Determine the minimum height and width of your box. Measure the frame diameter of your woofer, or check the mounting template that may be included with the owner's manual, to determine the minimum height and width for the front of your box. If you plan to mount a grille, be sure to allow for any additional space that may be needed to accommodate it.
3. Determine the available space in your vehicle. Measure the height, width, and depth of the vehicle space that you are willing to devote to your subwoofer. If the box must be wedge-shaped to fit, you will need to know the depth at the box's top and bottom.
4. Sketch out your box. Now's the time to sketch your box on paper using the dimensions you've gathered. The box shown in this article is rectangular, but you may find that a wedge-shaped box fits better in your car or truck. Your sketch may look like one of these:

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/drawing2.gif

For our examples, let's use the following external dimensions:
1. Rectangular box:
Height: 13"
Width: 14"
Depth: 12"

2. Wedge box:
Height: 14"
Width: 18"
Depth 1: 5"
Depth 2: 8"

Determine the internal dimensions and volume of your box. The above steps identified the external dimensions of the box. To determine the internal volume, just subtract the thickness of the wood to be used for construction. If you're using 3/4" MDF (recommended!), then 2 x 3/4", or 1-1/2", will be subtracted from each dimension.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/drawing1.gif

1. The internal dimensions for our examples:

Rectangular box:
Height: 11.5"
Width: 12.5"
Depth: 10.5"

Wedge box:
Height: 12.5"
Width: 16.5"
Depth 1: 3.5"
Depth 2: 6.5"

2. Calculate the internal box volume in cubic inches. Based on the internal dimensions, you can calculate the internal volume of the enclosure using the following formula:
Height x Width x Depth = Cubic Volume


Let's put some numbers in:

a. Rectangular box:
11.5" x 12.5" x 10.5" = 1,509.375 cubic inches

b. Wedge box: Since the wedge box has two depth dimensions, we need to find the average depth before we can determine the volume. To find the average depth, add the two depth measurements together, then divide by two. Remember that Depth 1 = 3.5 and Depth 2 = 6.5.
3.5" + 6.5" = 10"
10" / 2 = 5"

So, the average depth of the wedge-shaped box is 5". Plug that dimension into the formula:
12.5" x 16.5" x 5" = 1,031.25 cubic inches

3. Convert cubic inches to cubic feet. Since most manufacturers will provide the recommended box volume in cubic feet, you'll need to convert the internal volume from cubic inches into cubic feet. This is done by dividing the cubic inches by 1,728. 0.

Rectangular box: 1,509.375 / 1728 = 0.873 cubic feet

Wedge box: 1,031.25 / 1728 = 0.597 cubic feet

4. Adjust your box's volume to match the sub's specifications. Now, compare the volume of the box you've sketched to the manufacturer's recommendation. If it's too large or too small, you can make small adjustments to one dimension until your box's internal volume matches the manufacturer's recommendation as closely as possible.

Often, manufacturers will recommend a range of enclosure volumes. You can get good results with a box that's anywhere inside the recommended range.

5. Determine the final exterior box dimensions. Once you've identified the correct internal dimensions, it's time to add back that 1-1/2" we subtracted in step 5, to derive the new external dimensions. Double check to make sure that these dimensions will fit properly in your car, and you're ready to move on to construction!

Step 1.
We started by measuring and cutting the main pieces of MDF for the front, sides, back and top of the box, using a table saw with a carbide-tipped blade. Don't have a table saw? Don't worry. If you purchase your MDF at any large home improvement store, they should be able to cut it for you for a small fee. You could also use a jigsaw, but your cuts may not be quite as smooth (and smooth, flat cuts help to ensure that the box seals well). We cut seven pieces total — top and bottom, two sides, the back, and two identical pieces for the front (since it was to be a double thickness).

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_tablesaw.jpg

Step 2.
After the pieces are cut to size, use a compass, or the template that may be included in your subwoofer's packaging, to mark the woofer cutout on one of the identical front pieces.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_drawing_cutout.jpg

Step 3.
If you choose to use a double-thickness of MDF for the front panel (this method is recommended — it provides an extremely strong, non-resonant mounting surface for the sub), fasten the two identical front pieces together using plenty of carpenter's glue and several sheet metal screws. Also, the double thickness will serve to strengthen the box as a whole.

(If you don't use a double thickness of MDF for the mounting surface, you should definitely plan to use bracing elsewhere in the box for added strength. In fact, it's never a bad idea to use bracing no matter what, especially if your box is larger than a cubic foot. The box will be subjected to extreme internal pressure, so the stronger it is, the better. The easiest way to add bracing is with 2"x2" strips of lumber. Glue and screw these along at least two of your box's internal seams before attaching the top and bottom.)

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_fastening_fronts_together.jpg

Step 4.
Using a drillpress, we made a hole near the inside edge of the circle we had traced, large enough for our jigsaw blade to fit in. If you don't have a drillpress, simply use your handheld drill and a large bit.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_drill_press.jpg

We jigsawed out the circle, and the woofer cutout was complete

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_jigsaw.jpg

Step 5.
We followed the same drilling/jigsawing procedures to make a rectangular hole in the box's back panel. This would hold the terminal cup, which we installed next. After running a bead of silicon caulk around the edge of the terminal cup (available from Crutchfield, item number # 0732531034, $4.00), we screwed it into place using 1/2" sheet metal screws.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_terminal_cup.jpg

Step 6.
Since the back and front pieces were now complete, it was time to fasten everything together. Note: the largest sides of the box should overlap each of the smaller sides to provide the greatest strength. For our box, that meant that the sides were fastened to the front and back first, and the top and bottom were added last.

Because MDF can be prone to splitting, we pre-drilled holes for the screws in each of the pieces to be fastened together.
After pre-drilling the holes, we squeezed plenty of carpenter's glue between the pieces. The glue, not the screws, is what will ultimately seal the box together, so don't be afraid to pour it on.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_glueing_for_top.jpg

Then, we fastened the pieces together using our cordless drill and 2" drywall screws. Some of the glue will squeeze out during this step — you can wipe it off the outside of the box using a wet rag, but it's OK to leave it on the inside edges (it'll actually help with the seal).

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_screwing_top_on.jpg

After you put together the front, back, and sides, you may find that the box is a little out of square — we did. When you screw the top or bottom on, it should pull things back into alignment. Ours gave us just a little bit of trouble, though, so we used a furniture clamp to get things straightened out.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_top_on_with_clamp.jpg

After you've glued-and-screwed the sides, front, back, top, and bottom, you're just about done.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_all_sides_together.jpg

The next step is to drop the subwoofer in and make sure it fits. If the box has gotten a bit out of square, you may find that the sub is now a tight fit — if so, use coarse sandpaper or a rasp to enlarge the opening a little.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_rasping_cutout.jpg

Step 7.
With the subwoofer in place, we used a pencil to mark the screw hole locations, then removed the subwoofer and pre-drilled holes for the mounting screws.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_predrill_holes_for_sub.jpg

Step 8.
To make double sure that everything was sealed up, we waited for the glue to dry and ran a bead of silicon caulk over all of the box's internal seals. We used a hand-held tube of caulk, since it would be tough to get a caulk gun down inside the box at this point. Let the caulk cure for 12-24 hours before putting the subwoofer back in. Some silicon caulk releases acetic acid fumes while curing, which have the potential to destroy subwoofer surrounds.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_caulking.jpg

Step 9.
After the caulk had cured, we hooked up speaker wires from the terminal cup to the subwoofer and placed the subwoofer back in the box, using non-hardening rope caulk (found in the weatherstrip section of the hardware store) to seal it down. Don't use regular caulk for this — you'll need to pull that sub someday, and if you glue it to the box with silicon caulk it'll be tough to get out.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_speakerwires.jpg

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_ropecaulk_photo.jpg

Once the sub was in place, we fastened it down using 3/4" sheet metal screws, and our box was complete. NOTE: I (SeRiousZX2) actually use locking T-Nuts, but for basic box building, this is fine too.

http://akamaipix.crutchfield.com/ca/reviews/20030701/build_box/x_fasten_sub_to_box.jpg

There you go. From here you can do numerous stuff to the box. You can cover in carpet prior to installing the sub, you can fiberglass the front, you can sand it primer and paint it. Lots of stuff, be creative.

[conquest-king]

don't use silicone chaulking the fumes it puts off as it dries will weaken the speaker cone and the spider. I had a speaker blow prematurely because of this. Becareful!!! Liquid nails works good as an alternative.

[SeRiousZX2]

don't use silicone chaulking the fumes it puts off as it dries will weaken the speaker cone and the spider. I had a speaker blow prematurely because of this. Becareful!!! Liquid nails works good as an alternative.

Ummm, yeah I discussed that in the tutorial. If you use silicone, you must wait 24 hours before placing the speaker in the box.

[conquest-king]

It will still weaken the speaker because the first time it sits in the back of your car at +100* it will start letting out more fumes inside the sealed box. But i could be wrong.

[SeRiousZX2]

I have been doing this for 17 years the same way everytime on every box. Never had any problems.