Design MGM and MGU;

Note: During the design process, these numbers are determined based on a normal mast. Most masts have slight curves, these curves are not normally a factor but they can cause very slight variances in the stated numbers.

Some mast have extreme bends, when these curves are cut into the sails luff, they can make greater variances, as much as 6" in the stated upper MGU, ask if you have a question.

Normally, roach is the first thing designed into the sail. See other help topics on sail roach.