Tech Tips Archive

TECH TIP #4

PRODUCT UPDATE By Rod Carr (7/10/01)

Carr sails have been produced with tough, resilient polycarbonate headboards for several years. Recently we have seen a couple of mainsail head panel failures that occurred during uncontrolled gybes in high winds. Examination of the sails indicated that the failures occurred at the after lower corner of the headboard mostly in PX 75 cloth with its widely spaced fiber grid.

We are modifying our construction to include one layer of sticky-back insignia cloth under the headboard to strengthen the area, and by changing the shape of the after lower corner of the headboard from A to B as shown in the diagram below. We recommend skippers take a couple of steps to ensure the integrity of their existing sails. First, use a sharp pair of small scissors to round both sides of the after lower corner of the headboard as shown in B. Second, reread the tuning instructions that came with your sails and confirm that you are allowing the proper amount of twist in the mainsail in heavy air. The twist allows for shock absorption if you are inadvertently gybed. The two failed sails that we inspected showed signs of stretched leeches and luffs, indication of using too much tension on the vang and the downhaul. Downhaul tensions should be no more than 4 ounces for proper sail shape.