Broadseam

Broadseam is a term particular to the making of a sail. The panels that make up the sections of a sail are cut with curves on the connecting edges or seams. This method adds a three dimensional shape to what would ordinarily be a flat triangular or rectangular piece of fabric.

This technique was discussed in depth on the kitebuilders forum. Find more information here: http://www.kitebuilder.com/forums/viewtopic.php