Custom Sub

Having been frustrated at trying to purchase subwoofer pod for my hatch. I decided to
make one myself, out of fibreglass. The internet is a great help but here's a simple way
to make your own subwoofer pods, borrowing from many;

I chose the left rear as there is ample room for a ~35L enclosure without eating too much
of the hatch space, which was an important consideration for me. I also chose to design
for a 10" driver as this results in a smaller enclosure and I prefer a punchy/crisper bass.

You will need;

Around 5L of fibreglass resin, plus catalyst to suit.
3 sq m of 420gm chop-strand mat.
Half a dozen cheap paint brushes.
Stretchy material for the front.
Plenty of masking tape !
MDF for the base and spkr ring (I used 9mm)
Speaker Carpet (JayCar)

Step 1

Make a MDF base for the speaker pod, thankfully the hatch floor is flat so it makes
a great place to start. I cut mine with a jigsaw out of 9mm mdf, for a small pod this
is thick enough. Use 50mm masking tape and tape/mask up the whole area, and
then some, the tinfoil is good for protecting nearby stuff If you look carefully
you can see I drew the rough outline on the tape...



Here's a wider view of the layout.



Before you do any glassing, move outside ! this stuff stinks And get a warm
day so the fibreglass goes off , 15C+...



Apply a layer of resin onto the tape with a paintbrush and then stick pieces of
the chop-strand mat to the resin, this helps to keep it from falling off. You only need
one layer of mat at this stage. Work resin into the matt until it is well penetrated
and stick it to the top of the MDF base. Build it up more in the corners for strength.
Then let this go off and cure for at least 2 hrs, then you can remove it...



Step 2

At this point you can pop it out of the car. Remove the masking tape asap as it tends
to leave some of its glue in the car carpet. Below is the pod with just one layer of
fibreglass done...



After it was out of the car I applied 3 more layers to build up the thickness. Its about
6-7mm thick at this point. I trimmed and test fitted it again....nice



Step 3

The speaker support ring is made form 9mm MDF and this one was cut by hand, which
is tricky, if you have a router you can cut a neater one. The pic below has the support
ring in place with only one mounting. I added another 2 once I was happy with the position
of the ring. The mounts a glassed into pod back, base and screwed to the ring, three mounts
about 120 degrees apart.



Step 4

Sorry no pic of this...

Stretch flexible cloth material across the front of the pod and attach to the rear with masking tape
or staples. Apply only resin to this cloth and leave it to go hard. Dont worry about the excess cloth at
this stage, you trim it off later. I applied 8 layers of resin to the inside and outside of the stretchy
cloth over period of a week, it ends up smooth and strong. Many others apply mat or chop-strand
but mine ended up very strong and solid without it. Cut the excess stretchy cloth so that it goes
around the face and behind by say, 30mm, then resin it down to fix it.

I gave the whole pod a quick sand and then stuck speaker carpet to it...
(with contact adhesive) Its an easy job that gives a good result.



Step 5

Trim and tidy it up....



Step 6

The inside is lined with speaker dampening material and at the rear are external terminals,
the sunken type, all sealed. I have an older Kicker F10A installed at present but I have
another driver coming to replace it.

Looks as neat as a factory install. Fantastic work

great DIY Geoff

that is so good!!! cheers for that looks tops

Here's what it looks like installed



And...



It sounds great with just HU drive, Pioneer 8950BT, but will be driven with another amp soon


Well I hope this helps anyone thinking of having a go Its not hard and cost be about
$200...

That looks pro mate. Good work.

You really should have used chop strand matting on the front as well though as that's what provides the structural strength. The resin is just the "glue". How solid is it though? Does it flex at all when you push down on it? Have you stood on it? I've made one of these for the corner of my boot and used no less than 10 layers of 225gm matting to make sure the thing was solid as.

Have to agree with using the mat on the front, I tried it this way on a previous car and had flex, so found that I had to apply a few layers of matting to the front to get it strong.

But great write up, well done. Would be getting hard to find a +15 deg day in Canberra at the moment to get the resin to go off.

I did agonise over whether I should use chop-strand on the front or not, as everyone else
does it, but a mate who worked in the business said it wasnt as necessary as ppl think. The
front doesnt flex and you cant deflect it a mm by hand. Remember its a small
sub, that makes a big difference inthis instance. I dropped the thing (by accident) and it bounced

Aus301: Acoustically a small amount of flex wont hurt much if you have sound deadening
on the same surface, I have that polyester material inside and carpet on the ouside. We
played around with running it with no dampening, before the crapet, sounded ok ??? wtf.
With the lining and carpet it lost any 'ring' it may have had.

Fantastic job!

If you keep the copy of the sub box, and had it reproduced a few times somehow, could made a little cash

Look like a pro job, well done

Great job! Looks like a pro job as the others have already mentioned.

When you said it cost $200, is that just to build it, or does that include the driver as well? Where did you get the fibreglass materials from?

Also, when you removed the glassed box from inside the car, did it just pull away from the tape?

Can I ask how you secured the box from moving around in the boot?

Fkn Sweeeeeeeeeeeet. So trying this later in the year.
Thanks for the write up fellow wagon owner!

If you dont mind me asking, how much did it set you back for materials?

mate that's fkn schmick, great job! very pro...

Hard to say exactly, about $200 all up for stuff I didnt already have in my shed
I had to buy fibreglass mat, resin, speaker cloth, speaker carpet, terminals, some
glue, tape...the rest, like mdf , screws, etc I already had lying around.

awesome writeup mate...something ill be attempting in my car soon! i want 2 10" one on either side of the boot!

how did you get the fibreglass so clean and flat? just lots of resin?

Just even resin and minimal sanding

nice DIY mate

Top job, now, I need one for a 13.

Provided the driver doesnt require a large enclosure, adding another 10L makes
it pretty big...

Nice work man!!!

Yeah Top work man... You could sell those easily... Would love one for a 12 but. Anyone know of people/companies who sell them?

There is a company called "Karatan_Enclosures" who make and sell them on ebay.

They have buy it now for $250, but their bidding ones generally go for around $100-$150.

Geoff, that thing looks so fitted that I was expecting a FHI part #. Very nice work. How's it going with the cooling system?

C:\>

I just finished making my custom fibreglass subwoofer box as per the instructions in this thread and thought I'd say thanks for the great write up and dig up the thread for others interested

I'm not going to reinvent the wheel and repost all the steps required (just see the first post) - so anyhoo here it is, all hand crafted, with the 12" Sound Stream sub mounted and the enclosure wrapped in black vinyl

I will be mounting it in the car and wiring it up next weekend when I have a moment and I'll post a few more photos of the completed install

Front view (I had to drop the right side a fair bit to clear the left boot bracket):


Side view (a little rough looking at the back, but no one will ever see that ):


Front view (from ground to help show mounting angle):


edit: P.S. The lighting, reflections, grain of the vinyl and the few dusty spots on the vinyl are very misleading as the enclosure and vinyl covering is actually very smooth.

Man, that looks outstanding ! Brilliant.

Well done. I'm glad the instructions worked for you too, the pics look great.

Where did you get the sub driver ? how much ?

I like it way better than mine

Cheers mate. But the credit should be for you - without your instructions I would have a square MDF box like most others

I was originally going to cover it in carpet like your enclosure, but when I went and checked out the automotive carpet it was not very flexible and I was worried it would not stretch to the contours of my enclosure, so I used vinyl instead

I can't remember the exact cost of the Sound Stream sub, but when I get home from work I'll check the receipt and post the cost.

My next big job is to install everything in the boot - I'm going to make a whole new boot covering in black vinyl so that the sub enclosure blends in better, and then see if I can mount the amp under the parcel shelf out of sight.

Thanks again for the guide

WOW - that is awesome ...
thanks for the great thread ... i loved it soooo much i myself went out and paid someone to do it for me .. haha

will post pics soon ...

wtf? couldn't wait for me you lazy bastard? ah thats ok, post pics asap

seriously ... If i waited for your lazy ass ... it would be time for a new car!

on a more serious note ... how have you made ur sub box stay in it's position .. mine flips on hard turns to the left .... and ends up upside down ...
pics ...

mine's velcro'd to the side...a few strips...sie and bottom

how much was your's here Troyboy, just trying to compare buying vs. making as i pretty much have about half the parts to make incl sub and amp etc

Same, I will be using Velcro too

sub and amp won't make any difference to price of the box ... Just take ur specs of sub and he can work out the rest
Cost me $270. Dropped off car Monday - took car home that afternoon. Box was ready around lunch the next day.

Thanks for the tip ... Velcro aye ... just the sticky stuff??? on the the sub box and then they just anchor themselves to the existing carpet in the boot???

Yeah, just the 'loops' which stick to the interior carpet quite well.

so this box is about 35L and doesn't need to be ported?

A big thanks to larrikinstreak for all his help with my sub box.
Fantastic DIY this was my first fibreglass project and I think it turned out pretty well.
Here are a few pics from the process.


This masking job was a PITA.


First layer added.


Sub ring fitted after I had finished applying a few more layers to the base and back were finished.


Speaker cloth stretched over the box to get the front shape.


Layer of resin applied to the speaker cloth.


I used some bog to get the box nice and smooth


I had some matt black paint laying around so I gave it a quick flick to tidy it up a bit.






All finished and fitted.

Total cost ended up being about $230 (still better than the $375 quote from my local audio shop and I learnt something new)

Cheers

Really nice result, classy and functional. How's it sound ?

Top work for first time effort !

Geoff.

hey guys just wondering am i able to get all these materials from the local bunnings. if not where can i get it from..?

Personally I wouldn't go to bunnings they are a bit expensive as they just stock diggers prepacked stuff (well the ones in canberra do). Try to find a fibreglass specialist or a place that repairs boats or something they will usually have cheaper prices as they buy in bulk.

For example:

1sqm of medium chop strand matt
Bunnings = $22
Fibreglass specialist = $8

Resin
1L @ bunnings $30
4L @ Fibreglass shop = $70

I'm guessing you are no where near Canberra if you are I recomment you go to ACT fibreglass suppliers. Just search your yellow pages for something close to you.

Definitely agree with Puma on this one. The amount of fibreglass (resin mainly) needed for this job is a little more than handyman amounts, so buying from a fibreglass supply shop will be cheaper and more convenient.

yeah there is a lot of a difference there. there is a fiberglass place not far from me so ill get it from them. how much resin will i need roughly for a 12inch sub..?

I used about 5-6L all up I made mine pretty thick and I did stuff one part up and had to redo a small section so I ended up using more than what would normally be required.

I suggest you start with 4L (if they sell it in that size) than see how you go you won't get through 4L in a day as you need to let it dry/set before applying the next layer.

Speak to the shop as well they should be able to give you advice on how much catalyst to add to the resin for your current climate too.

Any questions flick me a message I'm more than happy to help.

ok so i started the pod yesterday afternoon. it was actually alot easier than i anticipated. i half expected all hell to break loose but it all went pretty smoothly. i got the first part done and got the pod out of the car redy to strenghten. just a quick question what should i use to trim the fiberglass and to cut a hole for the terminal port thing (sorry about the noob terminology lol)


Thanks for the help

It might be too late now, but if you do it yourself, don't make the mistake I did and take it out of your boot too early.

If you don't let the sides cure fully and have them re-enforced while they cure, and you take it out of the boot too early, they will sag a little. Nothing noticable when it is out of the car, but definately noticable when it is back in.

I took mine out a little early, fiberglassed the top and when it finally all cured and I test fit it in the car, one of the sides sagged in about 3cm and so there was a gap. Pain in the ass to fix actually, so I just covered mine and left the gap until I had some spare time to fix it, but I CBF atm

Anyhoo, just a little warning that may help.

Yep take the mans advice.. Mine did the same thing!

The bottom of mine bent up and wouldn't touch the floor. I had to cut the bottom off and re attach it. Luckly I test fitted it before I started putting the front on.

You can see here in this pic where the back and side meets the bottom that there is a thicker and lighter strip. The good thing about it though is now that it is finished you can't tell that it was ever done.

yeah i actually left it in the car overnight and pulled it out thismorning so its pretty rock hard.

Good stuff just to be sure just check the fit before you start putting the front on as it will be harder to fix once it's on.

yeah probably a good idea to stick it back in there before i go and finish it off.

thanks for all the help puma god knows where it would have edned up.

so its pretty much all done just waiting on dynamat and carpet from ebay. will post pic of it all complete.

Far out you have done well to get it made pretty quickly.

Post some pics up keen to see it!