hello,
just ordered a mb quart raa2400 amp with mb quart 12" sub and want to make a custom fiberglass enclosure....my question is....how many layers of fiberglass do i need to use to ensure that my sub doesnt crack it. I saw 3-4 in the how too for fiberglass interiors but didnt know if that would be enough for a sub box or not

thx
storm

A good rule of thumb is about 1/4" thick, with that thickness being thicker or reinforced in the flat areas. You should be able to stand on your sub enclosure without it flexing.

yeah 1/4" should set u up fine

I forgot to add that 1/4" is a general rule of thumb. If you're running some huge setup like Twin 18" RE XXXs off of 4000 watts RMS, you'll of course want something thicker. >>

I have made a few were only 4-5 layers have been fine. The one im making now i will prolly do around 4-5 cause the size, but will also test for the sound.

Are u building it completely out of fiberglass? Besides the 1/4" rule of thumb remember fiberglass is strongest on curves, and any area where it is not flat... so besure to mat the flat areas more than the curved areas.

I used 3 layers on my gen 7 celica 190 (GTS) and ir was fine pushing 1300 watts