foam or glass?

lets say you wanted to make the strongest 25lb board possible: would it be more beneficial to use a higher density foam and less glass (clark “classic” and 2x6oz) or lighter foam and more glass (clark spr green and 2x10oz)? im not sure of the numbers and what the actual weights of each would be (havent shaped a board yet) but its a hypothetical- whats more important- the foam or the glass? ive heard the analogy of lightly glassing concrete or heavily glassing a sponge, but ive found that analogies, when taken to the extreme, dont always hold true. i tried to check the archives on this, but i wasnt what to type for the search thanks johnO

John, I’ve tried both: Superlite foam and heavy glass, and Classic foam with normal glass. The results were that the lighter foam ended up with a lighter board, although I used two layers of 6oz. on the bottom and three layers of 6oz. on the deck and not 10oz. as you proposed. Eventually, though, the deck started to depress next to the stringer. It seems that the glass couldn’t overcome the weaker foam. I think, if you want a durable board, epoxy would be the best choice as the foam gets lighter and weaker. On the Classic foam board, 8oz. s-glass was used and the result was a very strong, but heavy board. Fortunately, the shape was correct enough to allow good turning and fast trim for the 265lb. guy it was made for. With poly boards, one of the best things to do to make them last, is to shape the deck with the least possible removal of foam. That way you’ll avoid a lot of the pressure dings and caving that happens with either over-shaping, or a soft blank. Doug

so doug, given the same weight, you think it’d be more beneficial (stronger) to go with dense foam than more layers of glass? just checking- im planing on using greg l’s resin research on a longboard, but it’d like it to have some weight to it (dont want the surftech feel). thanks for the info john

John, If you want a strong board with some heft to it, definitely. But remember not to over shape the deck. Even the strongest foam can cave in if you cut too deep into the blank where the foam gets softer. Incidentally, a guy I surf with is good friends with Skip Frye, and has several classic Skip designs. He said that Skip only uses Classic foam on his larger “glide” boards. Smoooooooth, and they trim fast. Doug