Cheap & Easy Custom-Fit Sub Box

I personally like when a car customization looks as though it belongs in the car - not out-of-place or gaudy. I also like (when possible) if a customization adds more all-around benefit to the vehicle than takes away. Some custom speaker boxes look amazing, and take up an amazing amount of trunk space. I like my trunk space, and wanted to keep it while adding a subwoofer box.

I own a 94 Chevy Camaro, and wanted to make a sub box that filled the empty space left of the  t-top storage cavity. The right side of the trunk houses the spare tire, but the left side is empty. There are few commercially made enclosures available, but many of them are designed to fit smaller subwoofers , and are more of a box shape, so they don't utilize all the available volume. Plus I like making stuff, and I had access to all the stuff I needed to make one myself - so that was reason enough for me to make it myself

The cost is largely dependent on what you need to buy - and the size box you intend to make. The materials I used to make mine total around $30 (polyester resin, a few cheap brushes, chopped strand fiberglass, paint) 

being that you will only use a small portion of the material in many of the containers, if you are buying all the materials for the first time, it will cost you more, but you will have a bunch of left-overs, so bottom line is, its hard to put a set number on cost

Step 1: Materials Needed

Materials Needed: [the consumable stuff]

Cardboard - [could be corrugated or non] 
Packaging Tape - [the wide clear stuff - 2" -4" preferred]
Fiberglass - Chopped-Strand Mat is easier to contour, but fabric is fine too
Polyester Resin - AKA fiberglass resin
Cheap Brushes - sometimes called "chip brushes" (used for removing chips from machining parts in a shop)
Paper Cups - multiple sizes are preferable (i prefer paper because they don't have ridges to catch material, but plastic is ok too) 
Stir sticks - popsicle sticks, tongue depressors, scraps, whatever is accessible 
Speaker Wire
A Speaker - or at least knowing what size hole for a speaker you don't have yet

Optional Materials: [more consumable stuff that makes it "more betterer" - yes betterer]
Body filler - bondo, or other brand
Paint - textured paint can hide a lot of flaws and will be your friend - if you are more meticulous and ambitious, go for high gloss :)

Tools Required: [the bare-minimum non-consumable stuff]

Scissors - heavy duty enough to cut cardboard
Hand Saw - hack saw or other relatively fine tooth type
Drill and drill bit - size dependent upon your project specifics 
Sand paper - Rough /coarse to medium [50 grit - 200grit should be sufficient]

Tools Preferred: [the "makes the job easier" non-consumable stuff]

Dremel (or other type of rotary tool)  with cut-off wheel
Grinder 
Power Sander

Comments

[jajoffer]

Great Instructable, I really appreciate high quality images. It annoys me to no end when people do not take the time to capture well lit, in focus, and relevant images.
Kudos, your good work is appreciated.

[The End of A Heartache]

very nice and very well builtand a great alternative to fiberglass building bass box.

I think you should have used MDF as a main support for your box building. Cardboard is a great idea. I used to build costume box and we used to use Plyboard for full on speaker box housing or MDF for small costume builts.

If you want to make a costume look, cut the front off, screw some MDF 1x2 for structure, cut and router a ring to hold the bass and more MDF to make holding structure, bring the ring out alittle to make it more costume. Take an old shirt *color doesnt matter as long as it doesn't have holes* stretch it out on the MDF frame from the ring to the fiberglass wall dont stretch it to much, just enough to give you a nice bounce back when you tap it, Nail it on then drip resin on it, lay 3 layer of fiberglass and then bondo it, sand it smooth and test fit.

It gives it a more costume look to the build. Stands out more compare it to a flush look. Also if you want play around with the direction the bass is pointing. If you up for acouple days worth of work you can make hit the way you like it by using direction to make it more acustic :)

[EH2200]

Thanks for all the suggestions, but my goal was to keep it flush and not visually stand out - If you have a chance, read the first couple sentences of my write-up and I think you will understand what I was trying to accomplish and why I built it the way I did

[mwwdesign]

Great 'ible.

Well documented and explained, although from an audio perspective, when making sub boxes, you need to pay closer attention to the recommended volume of the driver (speaker/woofer), and either find a volume to put the box that will fit, or you can find a driver that requires less volume. Also, the volumes can differ for each driver based on whether you install it in a sealed or ported enclosure - and yes, filling with dacron or the like helps with sound regardless too.

Either way, this is a fantastic lesson in how to make a custom fibreglass enclosure.

Thanks :)

[EH2200]

I am certainly not an audiophile, so I'm curious to know what the margin of acceptable error would be in terms of sub box volume - and there being a noticeable change in perceived bass quality.

I have heard that the amplifier that you are using can make a big difference in sound quality as well... It would be nice to know how much perceived difference there is as a result of changing a few different factors.

I have MB Quart component speakers in the doors and backseat, but to be honest I have a hard time hearing the difference between good speakers and great speakers. There are sooo many variables, and it seems like the importance of some aspects get more attention than others.

You seem to know your stuff, so if you can shed any light on the matter I would appreciate it.

Thanks :)

[isacco]

Congratulations for this work. The idea of using cardboard to perfect fit the car space is excellent. The crafting stesp are well explained and the final finishing is very good.

[jondneumann]

Final product looks great! Basic build, nothing unneccessary and it's to the point. I like the stock look.

[iminthebathroom]

Nice and clean, think mine is the polar opposite with the not so blending cheetah skin. Yours is what I usually do, excellent craftsmanship!