If you decide to go with synthetic line for your lifelines (and more importantly standing rigging) one thing to keep in mind is the expansion of the line when the temperature changes.
I recently found out that the synthetic lines SHRINK when the temperature increases rather than expanding like almost every other material. The coefficient of thermal expansion is a negative number and is greater than SS wire. This means that if you tension the lines in cold weather, they will to too tight when it is hot.
This is especially problematic for standing rigging. With the temp goes up, the mast grows and the rigging shrinks which can lead to seriously over tensioning of the boat. The recommendation is that if the ambient temperature changes my more than 30º you should retune the rigging. That would not be too big of a problem in the PNW where the temperature does not often vary my more than 50º throughout the year. Back when I sailed in north Idaho, I could get 50º to 60º swings in a single day in spring and fall.
I recently found out that the synthetic lines SHRINK when the temperature increases rather than expanding like almost every other material. The coefficient of thermal expansion is a negative number and is greater than SS wire. This means that if you tension the lines in cold weather, they will to too tight when it is hot.
This is especially problematic for standing rigging. With the temp goes up, the mast grows and the rigging shrinks which can lead to seriously over tensioning of the boat. The recommendation is that if the ambient temperature changes my more than 30º you should retune the rigging. That would not be too big of a problem in the PNW where the temperature does not often vary my more than 50º throughout the year. Back when I sailed in north Idaho, I could get 50º to 60º swings in a single day in spring and fall.
