Hi Ed
The beams are .125" thick aluminium (standart is .070") heavier but much stiffer.
The boom is standart F18 product.
Carbon was too expensive regards the weigh saving.
I could have choose the inter 17R mast (30 feet instead of 32) but the efficiency of the mainsail would have dropped by 3%. You would be surprised how light is the inter20 mast.
Total cost is about the same as an F18. Extra for the mast was about 1500 $cdn.
I still have to change the forestay to get more mast rake. Also I want to bolt together the beams and their attachment because, altough everything is thight, the beam rotate.
The boat is just fine and the spinnaker run really increase the of the 18 square.

denis 101