Originally Posted by splitsurferjeff
I do shape a lot of surfboards and do a lot of board repairs, and this idea of just soaking fleece with resin doesn't sound sufficient. RESIN IS WEAK. All of the strength comes from the resin hardening into the hollow fiberglass filaments and keeping them rigid.
Your point is well taken, and I don't think anyone would disagree with you on this. However, you have to remember that most of what people are suggesting you use the fleece and resin method on are cosmetic pieces. They're not structural panels. I don't think anybody is advocating the use of fleece for things like body panels or structural supports.
The surfboards you make and repair are subject to a lot of stress - i.e. the weight of the rider, the beating it takes from the waves, being drug through the sand, etc… The fiberglass makes up the rigid structure around the foam core of the board, and it needs to be strong enough to resist these outside forces to maintain its structural integrity and still perform well.
The average speaker enclosure, console, or dash cover isn't subject to those kinds of abuses, and any kind of failure of the fiberglass would be cosmetic only, and wouldn't effect the structure or safety of the vehicle.
Also, please remember that in the examples I've seen, the fleece is almost always just a cover over a separate structure. In the case of speaker enclosures, the main structure is usually MDF and hardwood dowel. The fleece is just a cosmetic cover for paint or some sort of fabric cover to be applied to. In newer cars these components come from the factory made from 1/16th to 1/8th inch thick plastics. It's not a part of the actual structure, so it doesn't have to be that strong.
Having said that, however, I agree with you that just soaking some cheap fleece with a bit of resin and making an entire dashboard out of it probably isn't the way to go. The fleece and resin method should be reserved for cosmetic trim pieces that only need to maintain their own shape and structural integrity - i.e. consoles, speaker enclosures, door panels, etc… Anything that is subject to stress should be made of several layers of fiberglass cloth or mat, and reinforced with a substructure of some kind.