It would work, however to apply the fiberglass in that way is very time consuming. When you lay the fiberglass over the cardboard you will be left with a very inconsistant surface. Very bumpy and uneven. You will then need to sand it down and then put some more fiberglass down in the thin spots. Then you will sand some more and fill some more spots with bondo. Then you will sand some more.....you get the idea. I did this with my helmet. It may seem dificult to make a clay sculpt and cast it in plaster then make a fiberglass cast....not really. The difference between the two procedures is that when you make a cardboard model and cover it with fiberglass, you are left with something that you are not sure how it will come out, and you spend about 2 weeks on it, any changes you want to make are difficult. When you make it out of clay, you spend the week sculpting it, any changes take a few min. you know what it will look like and once you have it cast, the fiberglass can be layed down, after about 6 hours pull it, then the next day sand it down. When you do it the other way you will sand FOREVER. The second way you will do little sanding. If you want any more info PM me.
