cosmetic fiberglassing

I'm getting ready to do my first fiberglass enclosure.  Well, really the sub will be in a sealed cube made of MDF, but...that will be encased in a unit that will also be an amp rack as well. 

I know when you build a sub enclosure using fiberglass, you do the resin, then fiberglass sheet/mat to strengthen it to withstand the pressures that the sub will place upon it.  However...if the fiberglassing is purely cosmetic, can you just do the resin and bondo???

Jeff,

Thanks for the quick response.  I do have an understanding of fiberglassing that is why I asked the question I did.  Without adding the matting, the resin still becomes rigid on it's own, correct?

I guess you could say I'm making a cover because in the end, the cube that the sub will be in will be totally hidden.  Since what I'll be doing won't have any structural bearing...could I get away with applying resin to the fleece (a couple layers) and then going over it with bondo, or...should I apply at least one layer of matting???

Really...it's just for giving the entire enclosure it's overall shape the base will be MDF and the top plate will also be MDF.  There will be no weight put down on it, nor any outward pressure from the sub.

Hope you don't think I'm an idiot or anything, just want to make sure before I delve into this project as I plan on this being my last sub enclosure build for my car for a long, long time.

Mike

the resin wil be brittle and may crack without glass. go ahead an fab it up first. then test the strength. if not strong enough, use fg cloth. it will help and be quick.

THAT...is what I was lookin for.  Thanks, based on that, I'll just go ahead and put a layer of fiberglass mat on and then bondo.  That way, I shouldn't have any problems.

Thanks for the input.