Does twill weave cloth lay down flatter and hold less resin than ‘regular’ weave glass at same weight? It sure seems like that to me. It may also explain why I use less resin then the epoxy guidelines. Why isn’t twill weave used more in surfboard building?
I just read something the other day to that effect, more specifically that since the fibers don’t go up and down as many times, then the fiber over it’s whole length is straighter…It was a composites site, and they had twills where the fibers went over seven or nine perpendicular sets before crossing beck under… The site said that the theoretical best case is if the fibers ran the length of the laminate without crossing, like unidirectional, with the fibers pulled absolutely straight. Mase sense to me…
Drawbacks were the more they skipped before crossing under, the more apt to unravel the cloth was…also made sense…
My local plastics place just started carrying 2x2 twill 5.8 oz. carbon fabric. Hmmmmm…
Havard, Wells, you both are right. Twill weave produces a much better resin/ glass relation and if used with the right tools you can achieve excellent results. It is widely used in high tech applications because of its much better tensile strength and is quite cheap as it is used in very big quantities in many industries. It is a bit harder to work (it likes to trap air and 2 layers are near impossible to wet in one go) and it has lower compression strength due to it being thinner so you have to compensate with a patch. Its standard weight is 160g/m2 (there are heavier ones around too) and two layers of it equal roughly 1 layer of 6 ounce in weight. Used right its a killer.