These are the first boxes I made. I planned on using 8W3's
Taped up and covered in plastic. I also put up a couple layers aluminum foil. I used a piece of cardboard to give an angle to the base so the box can slip in place without removing the cargo organizer.
I cheat when applying the first layer of fiberglass. I initially use cloth since it's easier to work with. I use spray adhesive to keep it all in place, and after every bit I want covered has cloth over it I paint it with resin. The biggest drawback to this is that the shell doesn't like to pull away. I found by having multiple layers of foil it separates the foil layers and pulls away much easier.
Time warp ahead a little. These are the back part of the boxes. I've already done a lot of the reinforcing on it. I used chopped mat. Buy a box of 50 disposable gloves for this. Put on 2 pairs and when the outer pair gets torn, melts, or is just too sticky to deal with peal it off and put another pair on. The keeps your hands from getting messed up. And use a respirator- if you're set against it at least do the work outside on a breezy day.
Here are the shells in the car. I still need to cut them both back some, but when it's finished it should sit about 50% over the edge of the cargo organizer. There's a little gap above the fiberglass which is from the 1/4" thick cardboard I had sitting under it when I made it. I wanted to have some spare room to work with so I could wrap the front glass around and wrap the box in carpet. I might delay doing the front half until I have the subs in my hands to ensure they fit properly.
Here is the mdf ring taped up prior to mounting:
The take helps to keep the seating surface clear of any resin. If someone knows an easier way I'd be happy to hear it.
Here's the ring set in place with dowels.
Pretty basic. Hot glue gun, dowels and something to cut them with. I found it easier to make an estimate of dowel length, cut it and glue it to the mdf ring. Then when you position the ring how you want it you only have to glue one end. The glue flexes enough to allow any positioning of the dowel.
Here it is wrapped in a T shirt:
I used hot glue to hold it in place. Just glue one corner, then go to the opposite corner and work your way around until you have it tight with no creases.
But here are a couple pictures to show some progress on the passenger side.
Outside the car:
Inside the car:
I know it looks a little rough right now, but it should sand up nicely. I don't know the proper way to avoid resin all over the mdf ring, so I taped it up prior to stretching the fleece over it. The resin should be able to come off with the tape fairly easily. Also prior to stretching the fleece over I sanded inside and a little around the outsides. The roughed up fiberglass of the back half allows the front new part to attach to it a lot better. After it set up and I had a few coats of chopped mat on there I cut away the dowels inside and laid some chopped mat inside where the two pieces meet. I also dumped resin inside and swirled it around the mdf ring to ensure it is completely sealed in there. It's probably overkill, but I've read stories of guys hunting tiny leaks and I hope to avoid that.
Here's the first coat of "milkshake" sanded down and covered in black primer. I was surprised how much the black primer matches the interior. I've still got some sanding to do on it.
Here's a little closer with a fresh coat of primer. You can see a little resin got on the seating surface. The primer definitely makes it easier to see all the flaws.
I did the initial sanding and coat of primer on the other side Here's a picture of both in the car:
I ended up painting the both with the bedliner material. I'll have updated pictures of them soon.
And for comparison here are the 10's.