I don‘t know were to get it or the name of the right fiber glass i need.
Go to a professional and have them check it out for you. I live in Michigan too. :)
prolly a hunk of poopie dropped from an airplane
Fiberglass is glass fiber cloth with polyester or epoxy resin filling and coating it. You want a woven roving or weave and the resin to apply to it. You can go to any boating store or look one up. It is not easy to work with and boats are made in a smooth mold with colored resin applied first, then layers of resins saturated cloth. If you do not use a mold a tremendous amount of sanding is needed so that is looks acceptable. Wood is very fine for speakers, easy to work with and make changes. It is also less expensive, cleaner, and can be stained, painted, or cloth covered. It will also sound better.
I would suggest building the actual box from MDF, and molding that into the surroundings Much easier and cheaper. Designing a good box from strictly fiberglass while possible, is extremely hard, messy, and expensive. To top it off, odds are you will likely have a sub par box when all is said and done.
