I am currently building my second Petrel. The first one was constructed of 5mm African Mahogany strips and 6oz cloth inside and out.With additional reinforcements of graphite and kevlar hybrid cloth in the seating area and copious amounts of cloth under the cockpit rim.
There are two bulkheads one behind the seat and one in front of the foot pegs. Total weight 41 lbs. This time I am looking for a lighter build so have used 5mm cedar strips with bits of walnut for contrast. Have used 4oz cloth inside and out. So i decided to try to figure out how the weight is distributed between the glass, resin, and wood. When the hull was removed from the forms with one layer of 4 oz cloth plus two fill coats on the outside only, it weighed in at 14.5 lbs. I was thinking at the time , oh no most of the weight is probably in the resin and glass this hull will really be heavy once the inside is glassed. To my surprise once the inside was glassed with 4oz cloth and a 5.7oz graphite reinforcement that was 50 inches wide under the seat the total weight was 17 lbs. Huh so only a additiional 2.5 lbs. Most of the weight seems to be the wood itself. I have noted that one forum member removes his deck from the forms without glassing . I can not help but wonder what does it weight? Must be between 11to 13 lbs. best rh