: Ted's experiment doesn't address the strength per weight of the composites.
: Just the weight of the composite using relative cloth weights. Hopefully
: he will use his samples to give us a strength test too.

: In the long run we want to know if an equal weight of S-glass/epoxy composite
: is just a strong as the Carbon fiber/epoxy composite. I think not but I'll
: wait for the written report. If two layers of s-glass can be wetted out in
: the same weight sample as a single layer of carbon and be stronger than
: the carbon then I'll buy no more carbon.

I understood that. That is why I put in my $0.02, which is probably wrong, based on Ted's reply. It was always my opinion (based on no research, BTW, just blurbs I picked up here and there) that the reason CF was chosen for many applications requiring strong yet lightweight equipment was that it was pound for pound stronger (tensile strength) than FG. That would account for why a piece of equipment made from CF is lighter than the same piece made from FG.

To illustrate:

I don't have hard numbers, but I know that, pound for pound, aluminum is stronger than steel. Therefore, if you are currently making a part out of steel that weighs, say 20 lbs, you can make the same piece from aluminum with the same strength as the steel part and the aluminum part will be 15 lbs. If you look at the part you may notice that the steel part was 1/4" thick while the aluminum part is 3/8" thick.

To apply that to the experiment that Ted did, if you take 6oz FG S cloth and 6oz CF cloth and wet them out with the same epoxy mixture (as Ted did) I thought that the cured CF composite would be stronger than the cured FG composite and therefore, I was implying that if Ted had used, say for arguments sake, 3oz CF against 6oz FG S cloth he would have two composites of equal strength, however the CF would be lighter.

This is all moot, since reading Ted's reply to my reply indicates that CF is actually stiffer than FG but does not have a higher tensile strength, which was my assumption when I threw in my $0.02. Regardless of my assumption, Ted's experiment was highly informative as a weight comparison alone.

Paul