Some people have asked me recently regarding doing fibreglass panels rather than carbon. Personally I wouldn't but if there is a real cost saving the following might have be a bit of a guide.
As designed:
200 GSM Double Bias Carbon Skins
5mm 80kg/m3 PVC Core
Weight: 1.067kg/m2
Stiffeness: 31 kN.mm2
Strength: 41.53 N.mm/mm
E Glass Option 1:
300 GSM Double Bias E Glass Skins
5mm 80kg/m3 PVC Core
Weight: 1.4 kg/m2
Stiffeness: 25 kN.mm2
Strength: 54.17 N.mm/mm
E Glass Option 2:
200 GSM Double Bias E Glass
7mm 80kg/m3 PVC Core
Weight: 1.23 kg/m2
Stiffeness 31 kN.mm2
Strength: 50.32 N.mm/mm
Final Notes
1. These laminates and comments are equally applicable to the scow and foiler.
2. For option 2, some adjustments should be made to construction jig for the extra 2mm of core
3. Brian built his Scow with 60kg/m3 core rather than 80kg/m3. I think 60kg/m3 is a bit light and dents easily but it does save some weight (0.97kg/m2).