I need an enclosure shrinking device :)

[Kaptain]

Last year I custom built a sealed enclosure for my 08 Silverado that fits perfectly under the drivers side back seat.
5 sides of the box are constructed of 3/4" MDF and the top is 1/4" of fiberglass. The reason the top is made from fiberglass:
my 10" sub has a mounting depth of 8" and fires downward, I have 1" between the sub and the floor for xmax. 8" and 1" is 9, and I only had enough room for an 8.5" box. So if you imagine, the wedge shape box is 8.5" tall on one side sloping down to 6.25" on the other to follow the slope of the back seat. Now since the mounting depth of the sub is more than the box I build a dome out of fiberglass to accomadate the magent of the sub. The rear passenger cant even feel the fiber glass dome poking up into the bottom of the seat This box has been one of my best creations.

My problem:

I spent lots of time and $$$ to build this box because I did not want to use a shallow sub. And now I would like to replace the current sub for a new one, without building a new box.

Old sub required 1.0 cubic feet, new sub requires .60-.75 cubic feet.

Anyone have any idea's on how I can shrink the volume of this box???

So far I have thought of three:
+ Cut small pieces of MDF and glue them to the inside of the box.

This would work but I calcuated that it would take around 20 blocks of wood to consume .25 cubic feet. What if the glue breaks free? It will also be difficult to secure the blocks to the inside with screws.

+ Fill the inside with fiber glass resin.

This would work really well, as well as being painless; just mix and pour. However, it would probably cost around $80 for .25 cubic feet of resin.

+ Cut one side off and reassemble.

This would require carpet removal, cutting through the fiberglass top as well as internal bracing. I would be afraid of ruining the box during the cutting. I would also have to re-glass the top to the new side.


One other idea was to cut the 10" hole for a 12". Only thing I am worried about is this may change the clearance for the magnet and most 12's I have looked at have .5" more mounting depth. It could work, but this is plan C.


I am looking for painless inexpensive suggestions.

[stipud]

Styrofoam blocks

[mhyde71]

^^^ what he said
i am inclined to concur with that solution

[Misfire]

Wasn't there a material like fiber glass or insulation that you pack in there. Been a long time, but I thought you could.

[smgreen20]

I would cut out the hump and make a new piece to fit in the hole. On the "inside" side of that piece I would add the blocks to take up the volume required, then put in the new piece. Fill in the holes/gaps and after it dries, you can recarpet it w/o the hump and it will look good again.

The 1st piece you attach to the inside side of the "cover" piece will need to be a pinch bigger to secure the new piece to the box from the outside.

[stipud]

Wasn't there a material like fiber glass or insulation that you pack in there. Been a long time, but I thought you could.

Polyfill is used to emulate a larger box, so it wouldn't be ideal in this case

[Misfire]

Thanks stupid... I remember something going in there, guess in my old age the CRS is kicking in...

[longboard]

sand and fiber glass resin works a treat mix them up then pour into the enclosure

[Thunderdome]

Styrofoam blocks

exactly what I would do, no weght and you could glue or silicone it to the bottom and volume would be easy to calculate

[ttocs]

you do not want to pour straight resin into it. If you let it cure when it is too thick it will build up heat and warp/crack and possibly catch fire.

[scottn29]

2x4's will be the easiest way