Fiberglass Sub-box Walkthrough

[ean611]

green liquid is milkshake.

 

It's bondo + fiberglass resin + associated hardeners.

[fzxtreme]

Hm, is there anyone in the chicago land area that wouldn't mind helping me out as i attempt to built this? Ill supply all the neccesities and reward your services with large quantities of beer.

[Imrac]

Wanted to post a quick pic of my result: http://legacygt.com/forums/attachment.php?attachmentid=68364&stc=1&d=1243231869

I cut mine a little on the small side. And fleeced it instead of using MDF flat peice. Total cu was .54 feet Works great with my Infinity Kappa Perfect. Has really tight bass with very good lows. Was the first time I have worked with fiberglass and I think I made it way thicker than it had to be. I was able to stand and jump on the box with out it flexing one bit.

[Instanced]

I went a slightly different route. After making the mold, my friend and I floated a ring, and stretched fleece over the top to make a contoured mold.

 

How do you Float the ring ??? I'm thinking about making a set of these boxes for myself, and I think floating the ring will be less weight and will generally look better, but i'm having problems trying to figure out how to make the face of the box... here's the steps I came up with... someone mind telling me if they sound right?

1 layer of fiberglass down first, then the ring... maybe another layer of fiberglass, then the fleece... all of this work is done on a flat section and then you cut it to fit the box and then add internal layers and an external layer to bond the flat surfaced work to the custom molded box piece together?

 

is that the general process of doing it?

[al-gorithm]

http://volvospeed.com/Pics/Mods/fiber_sub.jpg

[Imrac]

How do you Float the ring ??? I'm thinking about making a set of these boxes for myself, and I think floating the ring will be less weight and will generally look better, but i'm having problems trying to figure out how to make the face of the box... here's the steps I came up with... someone mind telling me if they sound right?

1 layer of fiberglass down first, then the ring... maybe another layer of fiberglass, then the fleece... all of this work is done on a flat section and then you cut it to fit the box and then add internal layers and an external layer to bond the flat surfaced work to the custom molded box piece together?

 

is that the general process of doing it?

 

No, I used the floating method on mine.

 

Step 1, Cut out ring and mount where you want, like in al-gorithms post. I used some hot glue to hold it in place. ** Pic 1/2 **

 

Step 2, take fleece and stretch over the ring and the mold. Make sure you get all the wrinkles out. I started on the bottom flat side and stretched it over the top. Seemed to be the best way. (again I used hot glue, just enough to get the fleece to stay in place, you want the resin to do the actual structural holding.)

 

Step 3, Use alot of resin and soak the fleece, the fleece sucks up alot of resin, so be sure to make a fairly large batch. Also, there is no need to resin the center of the wood ring, just make sure you go far enough in to cover the wood. ** Pic 3 **

 

Step 4, Fiberglass, the face of the box a few times. 4-8 layers, you can do 2 layers at once, but don't try any more. Cut the middle ring out, a router with a flush guide works well. ** Pic 4 **

 

Step 5, Finish, either bondo/prime/paint or just sand semi-smooth and carpet.

 

Edit: Added Pics

[Instanced]

I can't wait to afford to build these ha! I'll post pictures of my process once I begin it.

[executor485]

I can't wait to afford to build these ha! I'll post pictures of my process once I begin it.

 

Could just buy my pre-fabbed one lol

[Imrac]

I can't wait to afford to build these ha! I'll post pictures of my process once I begin it.

 

It cost me about $125 for the materials, but I could have done it for a little less. I had most of the tools already, but I screwed up like 7 times on the wood ring, next time I would just try a jig saw instead of a router or dremel.

[Instanced]

Could just buy my pre-fabbed one lol

I couldddddd, but I really wanna float the ring... and it's a good skill to aquire. I'll be doing your whole process with minor changes... one of which will be to put down the velcro pieces prior to masking off the car and laying the paper and aluminum foil down... that way when the mold its built... it will have "Indents" for where the velcro will go... should help it fit better as well.

[Imrac]

I couldddddd, but I really wanna float the ring... and it's a good skill to aquire. I'll be doing your whole process with minor changes... one of which will be to put down the velcro pieces prior to masking off the car and laying the paper and aluminum foil down... that way when the mold its built... it will have "Indents" for where the velcro will go... should help it fit better as well.

 

You can but its not necessary, the carpeting is forgiving and will flex, also when doing the fleecing part, you may want to bevel the edges of the outside of the fiberglass, or else when you glass the front you get a small lip. Thats what I have and you can see some of the small seems, but again, the carpet is forgiving and you just shove it in and it will look good.

 

Also if I didn't mention is before, get some spray adhesive, any auto part store should have some for head linear. Mask off the car, then take the aluminum foil and spray the back of it with a light dusting of the adhesive. Then place on the masking tape, that way you don't have any seams of tape that gets annoying to pop out. Make sure you get the edges of the foil pretty good, or else the resin seeps under a bit and causes the foil to get stuck on the outside of the "mold".

 

Overall its a fairly easy project, just take your time. After the first layer or two, you should pop out the mold and continue to glass. If you get your mold too thick it becomes rigid and difficult to take out. Work your way around the box I tend to do one side of the "triangle" at a time with some overlapping on the edges, that way you can do 2 layers at once saving you time in the long run.

 

The First layer I used the cloth fiberglass, then used the chop mat later on, but you might get good results using the chop first. or you might not, you can play around with it.

 

I would strongly recommend you get a respirator, even through my respirator you can still feel the effects of the odor. I think I may have used the filters too long because towards the end of the project I could feel my throat close a bit and I also got a sore throat. You should also wear eye protection, without it, you can feel your eyes start to burn.

[Instanced]

You can but its not necessary, the carpeting is forgiving and will flex, also when doing the fleecing part, you may want to bevel the edges of the outside of the fiberglass, or else when you glass the front you get a small lip. Thats what I have and you can see some of the small seems, but again, the carpet is forgiving and you just shove it in and it will look good.

 

Also if I didn't mention is before, get some spray adhesive, any auto part store should have some for head linear. Mask off the car, then take the aluminum foil and spray the back of it with a light dusting of the adhesive. Then place on the masking tape, that way you don't have any seams of tape that gets annoying to pop out. Make sure you get the edges of the foil pretty good, or else the resin seeps under a bit and causes the foil to get stuck on the outside of the "mold".

 

Overall its a fairly easy project, just take your time. After the first layer or two, you should pop out the mold and continue to glass. If you get your mold too thick it becomes rigid and difficult to take out. Work your way around the box I tend to do one side of the "triangle" at a time with some overlapping on the edges, that way you can do 2 layers at once saving you time in the long run.

 

The First layer I used the cloth fiberglass, then used the chop mat later on, but you might get good results using the chop first. or you might not, you can play around with it.

 

I would strongly recommend you get a respirator, even through my respirator you can still feel the effects of the odor. I think I may have used the filters too long because towards the end of the project I could feel my throat close a bit and I also got a sore throat. You should also wear eye protection, without it, you can feel your eyes start to burn.

 

Thanks for the heads up I'll be sure to buy both along with gloves and some poncho's (I have a nasty habit of working on crap like this with nice clothes on and turning them into not so nice clothes)

[rao]

I just made my first fiberglass sub enclosure I used the tips in this post and all of the other I could find which helped a lot.

 

I must say that it is a monumental PITA. I am sure like most things it gets easier with experience but it is messy and generally nasty. I would make another one but only if I couldn't fine someone who makes them (which was the case here).

 

The most difficult part was figuring out how to attach the cloth to the box and not screw up the shape so that it wouldn't fit afterword. Also I overbuilt the box just a bit (I could use it for a jackstand) and there was no way that staples were going to go into it so I used hot glue for the fabric.

 

Thanks for the info.

[executor485]

You shoulda PM'd me rao... I still make these boxes I actually made molds so that I dont have to tape up my car each time I want/need to make a new one.

 

I found a 3M spray glue that works GREAT for holding the carpet on the box, but hot glue works too

 

You should also post some pix, wanna see your handiwork

[rao]

You don't make them for a BMW e36 sedan

 

I already have one in my Legacy

 

There is no way I am posting pics of this thing

[executor485]

You don't make them for a BMW e36 sedan

 

I already have one in my Legacy

 

There is no way I am posting pics of this thing

 

Well I "would" but I'd need the car first lol

 

Come on, it cant be that bad... I'm pretty sure we've seen worse. Besides, if it looks like hell, we can just tell you that "it'll buff right out"

[rao]

I screwed up with the fabric and cut too much out from the speaker opening

 

What I had before:

http://img687.imageshack.us/img687/3092/dsc06838w.th.jpg

 

The new creation:

 

http://img706.imageshack.us/img706/9581/20100413subbox.th.jpg

 

http://img710.imageshack.us/img710/1421/20100413subbox2.th.jpg

[ean611]

Actually, that looks very good.

 

Nice job!

[executor485]

Not bad rao, not bad at all... I'd totally rock it

[spartan]

Do you make boxes for wagons or only sedans?

[executor485]

Do you make boxes for wagons or only sedans?

 

I only have the molds for a sedan atm... BUT... With that being said, I'm also working with ClimberD to get a wagon version. We are in the process of putting his car back together, so it wont be ready any time "soon" (I say soon meaning probably at least 2 months until we get a mold). But once we actually get his box(s) made, I should be able to have a working mold that we can use for a wagon version.

[rao]

I redid the carpet because it was making me crazy. It looks better now

 

The cut in the carpet to the left is from the dipsh!t that owned the car before me - they cut it to get access to the rear shocks when all you have to do is peel the carpet back

 

 

 

http://img718.imageshack.us/img718/6656/20100417recoveredsub2.th.jpg

[underground000]

I redid the carpet because it was making me crazy. It looks better now

 

The cut in the carpet to the left is from the dipsh!t that owned the car before me - they cut it to get access to the rear shocks when all you have to do is peel the carpet back

 

 

 

http://img718.imageshack.us/img718/6656/20100417recoveredsub2.th.jpg

 

the cut:

i would use gorilla tape (havent used duct tape before ) and tape the back of the carpet so it wont be so noticable

[nightspeed98]

awesome work guys. be ordering mine soon lol... my kid won't leave me alone long enough and neither will the momma.

[underground000]

what are you guys using for the resin?

i went to wal-mart and bought Bondo Fiberglass resin, and Bondo fiberglass resin gel. 2 different packagings, the resin has strands of fiberglass in it, it says. both are green and a paste not liquid, to me its seems more like for what you apply to fleece and sand.

 

EDIT: i bought the right stuff now