After preparing our boat for Hurricane Debby and sitting out the storm we returned to the marina to find the yacht essentially undamaged but with a fair amount of wind-blow debris littering the deck. In the process of cleaning this junk off, I discovered that tail of our #3 reef line, 72’ of 7/16” StaySet, had parted at the goose-neck while the remainder of the coiled line was still firmly bound to the base of the mast where we had secured it for the storm. Inspection revealed that the line had been chafed through at the goose-neck (leaving roughly 17’ of line in the boom) evidently due to the wind buffeting the length of line between the goose neck and the secured coil during the storm. Inspection of the 1st reef line revealed similar chafe although not completely through and similar, though minor damage to the 2nd reef line and sail outhaul.
Our yacht is fitted with Isomat Spars including the NB-40 Boom section which includes four sheaves in the inboard and outboard end fittings to take the 3 reef lines and outhaul. The sheaves themselves are/were made of Acetyl, a hard plastic similar to Delrin. While I had replaced these sheaves after we purchased the yacht in late 2001, during the intervening years, unnoticed they had worn and become brittle—likely due to UV radiation—such that the edges around the circumference had become very sharp and chipped, similar to a serrated kitchen knife. In this condition, the lines were quickly eaten up by the prolonged buffeting during the storm. While the damage is distressing, the silver lining is that I discovered it while the yacht was safely in her slip and not when I was trying to set a reef in foul conditions at sea.
Needless to say, I have replaced all of the sheaves again, and lines, but this time with an anodized aluminum version, which are available from RigRite
, (albeit at $40.00 each for our boat!) and certainly will be more durable than the originals. An unfortunately costly "learning experience". I thought others might like a “heads up” on the matter.