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Old 20-01-2010, 10:52   #16
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Humm...

Induced Wind Loading

F= (A*Sf*Gf*V^2)/390

Where:

F = Horizontal Force in Pounds
A = Projected Area in Square Feet;
Sf = Shape Factor (.90 for round, 1.10 for Flat Plate);
Gf = Gust Factor (1.10 at Sea Surface);
V = Wind Velocity in MPH (Knots x 1.15)

Sample Calculation; Beneteau First 42 in Steady 25 Knots of Wind = 534#. In 50 Knots = 2,136#

Whether one can use the windlass to haul a yacht up to an anchor is less a function of the windlass and more a function of the anchor's ability to sustain loading as the rode shortens and the angle of pull on the anchor increases.
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Old 20-01-2010, 18:13   #17
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svHyLyte,

While I agree that the anchor will not be able to hold the boat until the rode is vertical, in the case of a singlehanded sailor, it may well be called upon to haul the boat towards the anchor for a significant distance. At some point when the scope becomes short enough, the anchor will pop out but a significant portion of the rode will have been hauled in by then. If it hasn't been, either there wasn't enough scope to start with or the anchor is too small, either way the situation wasn't good to begin with.

A good singlehander will take up slack, let the boat surge ahead and take up slack and repeat this process. This will minimize the loads on the windlass.
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Old 20-01-2010, 19:28   #18
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Quote:
Originally Posted by klem View Post
svHyLyte,

...A good singlehander will take up slack, let the boat surge ahead and take up slack and repeat this process. This will minimize the loads on the windlass.
As I believe I said:


Quote:
Originally Posted by svHyLyte View Post
As for hauling a yacht up to one’s anchor with a windlass, even in significant winds, that is really not so much an issue so long as one leads the rode through a chain stopper (as one should) and hauls as the chain slackens with each passing wave. As the bow rises to the subsequent wave and the chain tightens, the chain paw in the stopper, and not the gypsy and windlass drive, takes the load; and, of course, as the rode shortens, the tension in the chain is decreased, lessening the load on the chain stopper or windlass, until, up-and-down, one is only lifting the rode and anchor with the windlass.
Further to this subject, there is no reason why a "single hander" cannot lock the wheel, or activate the autopilot, put his boat in gear and have her idle forward, or even power her up a tad when the wind is really up, to take the starin off the rode and go forward and retrive the chain. l was able to do that on our 42' boat when all we had was an SL555 Manual Windlass and, at my age, I am no great physical specimen. With the Maxwell VW1500 power windlass we have now, it's even easier. Even better, for very little money one can install a wireless controller that allows one to handle the windlass from the helm (or with the newer RayNav and other Autopilots, a wireless controller that allows one to steer from the bow). I happen to use a "Quick" wireless controller that I can punch-up from the helm position from which I can see the chain markers as they roll over the bow--even at night--so I know when the anchor's fully aweigh and I can safely fall off..

For the sake of the discussion, as a teenager I was taught to "sail the anchor out" by hoisting the main--to the first or second reef if in really heavy winds--lock down the tiller amidships, free the mainsheet a few feet, go forward and haul the luffing main to one side of the mast or the other to get the boat moving and to go forward and get ready to heave in the rode--then by hand as we had no windlass--as the yacht surged forward. As she did so she'd snub up against the tightened rode on one side or the other and "tack", surge forward again, and more rode was taken up until the hook finally broke out. It's amazing how quickly one can then get the freed hook to the bows and then make it back to the cockpit to bear up or away, so long as one has a good chain stopper with loose paws to lock up the chain.

And Here Homer Nods...
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Old 25-01-2010, 02:06   #19
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Quote:
Originally Posted by svHyLyte View Post
...Further to this subject, there is no reason why a "single hander" cannot lock the wheel, or activate the autopilot, put his boat in gear and have her idle forward...
Unfortunately that approach doesn't work, I've tried it a couple of times on both my boats with no success. This will work with little or no wind - but in weather like that the windlass isn't loaded anyway. In 10 knots or more of wind where you would want to use this method the idle forward speed is just slow enough to give motion but no rudder control with a locked rudder. But that wind is strong enough to "grad" one side or the other of the hull while the boat sails around, and suddenly your boat is heading off at 30-60 degrees to the anchor line, which increases the tension on the windlass but now it is is heading off towards your nearest neighbour in the anchorage, so you need to run back to the helm again.
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Old 26-01-2010, 02:05   #20
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Having just been through the hoops of finding an Anchor Windlass that would fit my vessel was a pain. Most manufactures that I specified, i.e. Lofrans, Vetus, Lemar, Maxwell do not even make a windlass that will handle ALL half inch chain rode. And then factor in hydraulic and the playing field gets even smaller still. I finally had to make a decision on a high dollar Anchor Windlass that would handle half inch chain rode and would be plumbed for hydraulic operation. I have discounted a +12 Volt Windlass due to the added power draw and the larger wires needed for a vessel of our size. We are a center cockpit 46 foot vessel. Engine room is below the cockpit as are the ships batteries. I wanted to install a separate Windlass battery with battery charger in the Vee Berth but this was all too much weight forward. I have a hydraulic engineer on our dock that will do all the install of pumps and hoses. He and I live where fishermen live by the work a hydraulic pump can perform. Lighthouse Anchor Windlass print that their windlass can kedge 10-thousand pounds! That is pretty good advertisement for me. I have tried to kedge this 20-Ton vessel with an old Simpson-Lawrance Super Tiger and it is not fun. So I will pose this question. Is the cost of Battery powered Anchor Windlass the reason most manufactures do not make available a hydraulic version? Lofrans and Vetus once were available in hydraulic.
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Old 26-01-2010, 07:51   #21
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The Maxwell VW3500 can be had with a 1/2" chain gypsy. The hydraulic verson requires 2000psi at 11 gal/minute. The 12v version draws 1200 watts. From your engine room to the windlass would likely require 2/0 cable. See Vertical Windlass Range
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