Gaff Rig Design

[H/V Vega]

Hi Mate,

Look there is much more to rigging a hull with the best rig than getting a few pictures and what worked on another boat. The right rig must be designed for your hull and her specific center of lateral resistance. What looks great superimposed on the hull as she would float may not work at all under way. The center (s) of lateral force from the sail plan must work in careful harmony with the hulls center of lateral resistance or you get a dud. One quick and easy way to get the hulls center of resistance is to make a photograph taken exactly from off the beam and about half way from the keel to the waterline (use a normal lens no wide angles here please) when she is out of the water then cut carefully around the underwater body and along the water line. Balance that on the edge of a knife blade and you will have a very good idea of where the hull center of resistance is. Make your sail plan lead that center ever so slightly and you have a good chance of getting a boat that sails well. Hope this helps a bit.

[steven prince]

H/V Vega,

I do understand that you have to keep the rig balanced or you will upset thebalance of the boat. My boat isn't actually built yet. I'm in the process of designing it and then building it. I have the great advantage that I have created the design on a C.A.D program that will give me the two centers. The rig center is on roughly the same position on the X axis as the original rig (it's about 200mm further aft) but it is now lower than the original rig, but a gaff rig generally has a lower center.

I have been getting advice of several people to help with the design of the rig to ensure that it sails ok.

Regards
Steven