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Single-halyard control of peak and throat

PostPosted: Wed Mar 18, 2015 12:01 pm
by craig
File this post under the "interesting but of dubious utility" column. I was browsing the internet and found a unique way to raise the sail on a gaff rig by using just one halyard (located at http://thecheappages.com/boat/cob/COB_sea-boat.html):

COB_halyard.gif
COB_halyard.gif (5.43 KiB) Viewed 1848 times


Since the hardware already installed on Pocketship allows for quick conversion, I gave it a try in the driveway. The idea absolutely does work. When you get everything pulled tight the sail set beautifully. When I conducted this experiment the boom was lowered all the way to the cockpit (no gallows or topping lift). When the halyard is pulled, the throat tends to rise first about halfway until it is stopped by the heavy boom. The peak then goes all the way up, pulling the boom with it, then the throat finally reaches the top. You have to pull fairly hard on the halyard to get everything tight. If I had attached the topping lift to raise the boom up to its proper height, I believe the throat would have risen farther before giving way to the peak.

Lowering the sail is more challenging. The peak falls first and doesn't stop. Eventually the combination of boom and gaff puts so much tension on the gaff gooseneck that it won't lower even when pulling on the sail. I believed at the time that this was a fatal error and reset the rigging back to normal. However, I now wonder whether using a topping lift on the boom (as I have installed) would correct this issue since the boom would no longer pull down on the gooseneck. Also, I could simply be careful to slowly lower the peak and manually pull the throat down with a line or by gently pulling on the luff.

Assuming the jammed throat situation can be corrected, this setup could allow for very fast setup or take-down of the sail, or simpler control of reefing (play out 5 feet on the halyard, pull the jiffy-reefing line tight, and reset the halyard).