materials

i've designed a 5m catamaran and i am confused to what series of fabrics to use in the constructoin. i plan to use polyester resin and the first layer i plan to have mat. i need the cat too be light weight but not too expensive to build. can anyone give me some ideas on what alternet layers to put on? e.g mat (first layer ), woven roving ect.

 

well mate the cheapest way I have discovered to laminate using polyester resin assuming you are going for single skin is to get a duo matt which has chopstrand allready attached duo matt is a more complex type of w/roven. I have used 1 layer duo ( 2milmeters thick when wetted out at 1 of reinforcements to 1 of resin) then 1 d/bias 45 degx45deg then 1 more d/bias each layer has chop strand attached ,finnished thickness is 5 to 6 milimeters thick and weigh's about 6 kg per m2. But the cat hulls were over 10 mtr's and were elipse shaped and one piece moulded over a male mold . If your design has flat surfaces such as deck or gunnels it wont work. But I admit I know nothing and will be very interested in another opinion.