Jayhovah's fiberglass sub box build log
 

I have been brainstorming on what to do for a sub box for over a year... I originally had my heart set on a ported 8" setup.... At first I thought I might try and build an ultra light foam core box but it was going to take up way too much space... then I thought maybe I could stack fab an MDF box into the cavity under the floor in front of the shock towers, but sinking an 8" sub into that area was just going to be too tight for me(have seen others fit 8" in that area though)....

I finally decided to stop fiddling about and just make a simple sealed box for the Alpine Type R 8" that has been sitting on the shelf for many months. I absolutely hate working with fiberglass but you just can't beat it when it comes to weight and fitting things into odd/tight spaces. This will be my 5th fiberglass car audio project, so hopefully there will be some benefit from the experience.

Got started today - on to the pics!

http://www.the370z.com/members/jayho...masked-off.jpg

All masked off, used modeling clay to fill voids or round off sharp bends.

http://www.the370z.com/members/jayho...9-layed-up.jpg

Got the glass layed up...

http://www.the370z.com/members/jayho...popped-out.jpg

Here it is popped out. God I hate fiberglass.

Tomorrow I'll trim it up, make the baffle, and hopefully glass up the rest of it.

Looking forward to seeing the finished product. Make a second one to use as a mold in case I like it, you can make me one. :woot:

...
I'd say the chances of that are pretty slim... :tup:

Finished cleaning up my mess from the day and decided to mark up the mold for trimming so another small update before tomorrow...

http://www.the370z.com/members/jayho...t-fit-mold.jpg

Quick test fit and I realized I've already made a mistake... I made the mold with the top trunk mat out thinking with the weight of the sub should squash down into place when it's reinstalled and the box was finished... this was not entirely true and there is a little bit of a gap around the box towards the inside of the car (on the outside the contours of the panel hold it down in place). I think this will be OK though, as I plan to add some foam on the outside to decouple the box from the interior panels.. hopefully it will keep it fitting tight. In the worst case Ill have my trunk mat modified to remove the area under the box (and put a cut in the under-mat there)... that would suck, but it also carries the benefit of being able to access the spare without removing the sub (which would also allow me to screw the box in place). Not a huge deal and somewhat of a tradeoff.

http://www.the370z.com/members/jayho...trim-lines.jpg

I want to use a flat plywood piece for the baffle so I used a laser level here to mark the horizontal trim line... this way it all stays on plane.

http://www.the370z.com/members/jayho...trim-lines.jpg

Marked the vertical cut as long as I had the laser out...

http://www.the370z.com/members/jayho...dy-cutting.jpg

Ready for trimming!

Oops, I thought you said you love working with fiberglass. ;)

the use of the laser level is genius.......

Small update...

http://www.the370z.com/members/jayho...trimmed-up.jpg

Trimmed up the mold..

At first I thought I would do an all plywood baffle... but it would have to be double layer so I could flush mount the sub and would be difficult to glass in and probably a little heavy.. Instead I decided to do a mounting ring and glass it in.

http://www.the370z.com/members/jayho...-out-rings.jpg

http://www.the370z.com/members/jayho...jig-set-up.jpg

Cutting out rings with a jig saw is much faster than setting up a router and jasper jig..but there is something so sweet about perfect circles.

http://www.the370z.com/members/jayho...wood-rings.jpg

http://www.the370z.com/members/jayho...gs-cut-out.jpg

http://www.the370z.com/members/jayho...s-ready-go.jpg

http://www.the370z.com/members/jayho...ffle-rings.jpg

Set up with some wood glue and brad nails..

http://www.the370z.com/members/jayho...ir-bubbles.jpg

While waiting for that to dry and I ground out some of the really bad air bubbles in the mold and patched them over with a few layers of cloth.

Will see about glassing in the baffle tonight after my girl goes to bed... what do you guys think so far?

I think you should have made two (just kidding). Looks good so far. Hurry up and finish it so I can give you crap for not making me one. :stirthepot: :D

You might get lucky! I did a similar one in my 350z and decided I wasn't happy with it, ended up selling it to someone following that build thread!

I do the same thing. I build something and if it doesn't turn out exactly as I imagined I scrap it and start over. It took me three times before I was happy with the cubby gauge pod I fabricated. If it doesn't work for you we can talk. If I get my car back from Specialty Z next week I'm hoping to to have close to 600 supercharged horses to listen to for a while. :tup:

I see that you're finally getting to finish this project!

So jealous that you're able to work on your car at this time of the year. Every time I think of messing with my interior/fuel system, the weather motivates me not to (-5F currently)

It's gonna be redonkulous!!!! Looking forward to seeing your results!!

LOL that would be a deterrent!! temperatures dropped pretty sharply over the last couple of a days and its a brisk 55 degrees outside... Just took the car to walmart for some late night supplies and it always surprises me with the power on cold days.

The cooler weather is also giving me a lot more work time with the polyester resin...

You need a heater in your shop!!! If I had my car stored for the winter I'd want to do all sorts of stuff!

glassed in the top and started adhering the baffle. Taped off the surface of a table and used it to mold the top flat. I went ahead and glassed up one side of the baffle (the one closest to the opening)... I will see how well stuck the ring is and decide if I need to glass in the other side as well (which will be awkward).

http://www.the370z.com/members/jayho...p-baffle-1.jpg

http://www.the370z.com/members/jayho...p-baffle-2.jpg

http://www.the370z.com/members/jayho...p-baffle-3.jpg

http://www.the370z.com/members/jayho...p-baffle-4.jpg

In for the pics. Looking nice. I need to get one of those laser thing-a-ma-doodles. Very handy.

I'm with ya though... working with glass sucks.

Highly recommend it! It was a Harbor Freight impulse buy (~$45) and I am constantly finding uses for it.