Christy had a good point on slacking line while on a gypsy head or capstan/winch. I'd differ with the Dog and the American Trial Lawyers Association on this one,
If you need to slack a loaded line on a winch, the SAFEST way to do so is with the flat of your non-line tending hand against the face of the winch, against the turns. Obviously, you should not get your flanges caught between the line and the winch. In addition to allowing you much greater control of the line, the procedure is safer. The reason it is safer is because the alternative is the "flip the line" method which generally results in too much line going out, and is quite likely to allow the line to run on you. If you inadvertently flip off a wrap, it is much more likely to run on you. The sudden acceleration of the line is likely to catch up things with it. Like your hand, your ankle because you're inadvertently standing in the bight of the hauling part, and other objects.
I have witnessed cargo booms dropped on deck with this lazy "flip the line" method. One of the first rules of handling any line is to maintain control of the line; there are very few instances where an uncontrolled slacking of a line is desirable. Out of control lines tend to break things; either very expensive things or very human things. Watch the scene in "Men of Honor" for an illustration. It is important to learn how to control your lines when slacking as well as hauling. The human hand, or any other part of the body cannot react quickly enough to avoid a running line, or worse, a parted line.
Practise the procedure under light loads. Remember, as much as possible, keep your palm flat and your fingers as straight as you can and still accomplish the job. Keep your fingers together, much as if they were an extension of your palm. Avoid unnecessary wraps on any drum. If light hand tension will hold the line, take only one more turn. After that, you can run into a situation where the line becomes heavily loaded, the first wraps begin to slip, generating heat and begin to fuse to the drum. As you try to slack the line, the first wraps will suddenly break free, perhaps yanking you and your hand into the capstan. Better to have one turn too few, have the line slip a bit, and then take another turn if needed. Filling your winch up with as many wraps as she'll take can make it difficult, and hazardous, when it comes time to slack the line under load.
For more on lines (not rope), anchors, Portagees, and assorted asses you can visit the off-topic forum under "Asses and Full of Crap". It is a sailnet exclusive, where each of us has endeavored to prove himself the biggest ass on the site. As you've seen the competition is fierce. Enjoy!
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