PocketShip.net

Does any know what Safe Working Load or Working Load Limit you need for turnbuckles for shrouds?

You want turnbuckles that can handle at least the safe working load of the weakest point in the system the designer has specified. That could be either the 5/32 wire or the Padeyes -- I'm not sure which is weaker. I would just go with the safe working load of the wire (700 pounds I believe) and get turnbuckles that can handle that load.

For what it's worth, I read somewhere that 20 knots of wind will exert 1 pound of force per square foot of sail. Of course then you have to consider gusts, shock loads, damaged cable, etc, and put in the appropriate safety margin. I also believe the safe working load of the blocks used for the jib and mainsail have a safe working load of 350 or so pounds, but your question was about the shrouds, so that wouldn't matter I guess.

I am not sure what is required, but I just purchased 2 stainless turnbuckles from Duckworks that I plan to use for my shrouds that are rated at 1980 lbs breaking strength - each of the 2 could be used to hold the weight of my whole boat.

Based on Craig's response that should be plenty.

On page 270 of the build manual John calculates that lashing the shrouds with about 30 turns of 2mm spectra line is "brutally strong (4500 pounds)." That's probably overkill (that's per shroud), but might indicate what John has in mind.

Thanks for all the info. Got a couple of turnbuckles that appear to do the trick.