Originally Posted by Irie
Apologies if this has been discussed before, but a search did not pull up anything....
Is anyone aware of a formula or other guidance to determine what halyard breaking strength is required ? My main is old & stretchy, and was wondering if you could calculate the recommended breaking strength by using the displacement, P and E lengths.... is that too simple ?
Boat is a Tartan 3000 that we do beer cans in, and primarily weekend/weeklong cruises. Displaces ~3800 with a P (luff) of 34' 3" and an E (foot) of 11 ' 6".
Any brand recommendations are appreciated. The front-runners in my research are 3/8" Samson XLS Xtra (4600 pounds) and New England Ropes Sta-Set X (5500 pounds).
Thanks in advance !
Check out the http://www.westmarine.com/webapp/wcs/store...ging-Fibers.htm
. The chart is quite revealing that breaking strength is not the issue, but how much stretch you are willing to endure as the loads increase with the increase in wind. Having a stretchy sail in addition to a halyard that allows the head to move down moves your draft aft (baggy) and increases your heeling moment just as you want to move the draft forward and flatten the sails to keep her on her feet and moving well to weather.
Wire is the best (least stretch) followed by the V-12, T-900, dynema, etc. as shown on the chart.
We use, due to 94' mast, wire for our genoa, right on to the winch drum for the least possible stretch, and vectran for the main, spin, and control lines. The new materials allow generally a size or two smaller than what you are using now, and performance, particularly to weather, will be dramatically better.
Our J27 with nearly the same specs as your tartan, we use 1/4 main and 3/16" jib and spin vectran halyards, which are stripped for weight aloft, and only have the outer layer on for the winch and jammers. We have even gone to a 1/8" dynema backstay, which is stronger than the wire it replaced, and saved 12 pounds aloft, a huge reduction!
Take the high tech halyards off if you strip the cover, leaving 1/8" placeholders up when you are not actively using the boat. If not, the high tech line is 80% of its initial strength after 2 years continuous use, and does not degrade appreciably after that as the cover takes the UV.
best of luck, and enjoy the better performance!