I keep thinking I read about a way to rig up a mainsail downwind boom reversal preventor that only required a single line. This setup did not require the need to walk forward to switch the line to the other side of the mast. It might have used more than one line, possibly with a block, but the outcome was that it could be managed from the cockpit. Real or just a wishful dream? Ray S/V Speedy
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Somewhere, but where?
I think you are right Ray. I subscribe to both Sailing and CW so maybe that is where I saw it. Meanwhile there is some pretty good reading in the Link below. I'm still using my vang. I detach it from the mast base and reattach on the toerail. But I know there are better and safer ways. Which I will need if I ever go to a solid vang.
I think you are right Ray. I subscribe to both Sailing and CW so maybe that is where I saw it. Meanwhile there is some pretty good reading in the Link below. I'm still using my vang. I detach it from the mast base and reattach on the toerail. But I know there are better and safer ways. Which I will need if I ever go to a solid vang.
Boom brakes and another idea.
There are boom brakes available that essentially perform this function. The link below is one example. After giving the problem a little thought, however, I think I have an alternative: Imagine a line running from the midpoint of the boom to a block at the toerail just forward of the mast. This line goes through that block, across the boat to another block on the opposite toerail and is again run back to the midpoint of the boom. Both ends of the line are attached to the boom at an eyestrap or bail or something. Perhaps the same place as the vang, but the farther aft, the better. Call this the "preventer line". Now, at the front of the mast, near the step, run the line through another block. This block floats free and is attached to a control line that runs up the mast, oh 5 or 6 or 7 feet, maybe, to a turning block and then back down again to a cleat or to other blocks that guide the control line aft to the cockpit. When the boom is amidships, there is no slack in the preventer line. As the boom moves to one side or the other, the shape of the triangle formed by the preventer line changes and the line begins to get slack. If you pull on the control line, the block at the front of the mast will rise and you'll gather in that slack. The farther out the boom is, the more slack in the line and the more the control line needs to be pulled to gather in the slack. The boom cannot travel back to the amidships position (or across to the other side in a gybe) unless the control line is released. Hmmmm.... That's 15 minutes of cogitating. Might be better ways or better alternatives. You also better be sure to release that control line before you gybe! Also if you have a spinnaker pole, this stuff on the mast might get in the way of those controls. There's probably a more space-efficient way to control the slack in the preventer line. Thoughts???
There are boom brakes available that essentially perform this function. The link below is one example. After giving the problem a little thought, however, I think I have an alternative: Imagine a line running from the midpoint of the boom to a block at the toerail just forward of the mast. This line goes through that block, across the boat to another block on the opposite toerail and is again run back to the midpoint of the boom. Both ends of the line are attached to the boom at an eyestrap or bail or something. Perhaps the same place as the vang, but the farther aft, the better. Call this the "preventer line". Now, at the front of the mast, near the step, run the line through another block. This block floats free and is attached to a control line that runs up the mast, oh 5 or 6 or 7 feet, maybe, to a turning block and then back down again to a cleat or to other blocks that guide the control line aft to the cockpit. When the boom is amidships, there is no slack in the preventer line. As the boom moves to one side or the other, the shape of the triangle formed by the preventer line changes and the line begins to get slack. If you pull on the control line, the block at the front of the mast will rise and you'll gather in that slack. The farther out the boom is, the more slack in the line and the more the control line needs to be pulled to gather in the slack. The boom cannot travel back to the amidships position (or across to the other side in a gybe) unless the control line is released. Hmmmm.... That's 15 minutes of cogitating. Might be better ways or better alternatives. You also better be sure to release that control line before you gybe! Also if you have a spinnaker pole, this stuff on the mast might get in the way of those controls. There's probably a more space-efficient way to control the slack in the preventer line. Thoughts???
Similar idea
I once sailed a 30' boat with jib roller furling that had a continuous control line. The line wrapped around the furling drum 4 or 5 times, then led aft outside the port stanchions, around the stern, and back to the bow starboard side, where the two ends were spliced together. Furling and unfurling were accomplished by pulling the line in one direction or the other (there was enough slack in the line to cleat it off to keep the sail furled.) I can envision a similar idea for a preventer; of course no splice would be needed, since the line ends could terminate at the boom. BTW I read somewhere (Calder I think) that the preventer should attach to the boom at the same point as the sheet; otherwise you can bend the boom if you attempt to gybe and forget to release the preventer.
I once sailed a 30' boat with jib roller furling that had a continuous control line. The line wrapped around the furling drum 4 or 5 times, then led aft outside the port stanchions, around the stern, and back to the bow starboard side, where the two ends were spliced together. Furling and unfurling were accomplished by pulling the line in one direction or the other (there was enough slack in the line to cleat it off to keep the sail furled.) I can envision a similar idea for a preventer; of course no splice would be needed, since the line ends could terminate at the boom. BTW I read somewhere (Calder I think) that the preventer should attach to the boom at the same point as the sheet; otherwise you can bend the boom if you attempt to gybe and forget to release the preventer.
boom lock
Ray, I installed the Scott boomlock, referenced in the link Doug T listed, on my 410 this winter. It works as advertised and is a slick, clean installation. I ended up installing 2 padeyes near the jib tracks to keep the preventer lines clean. Except for the padeyes, which wouldn't be needed if you have a real toe rail, its a 2 beer install. Not only is it a lock, it easily jibes the boom when your ready. It has a single 1/8 inche spectra line run back to the cockpit for control with a cam cleat installed at a convenient point to keep the boom locked. Bryce S/V spellbinder H410
Ray, I installed the Scott boomlock, referenced in the link Doug T listed, on my 410 this winter. It works as advertised and is a slick, clean installation. I ended up installing 2 padeyes near the jib tracks to keep the preventer lines clean. Except for the padeyes, which wouldn't be needed if you have a real toe rail, its a 2 beer install. Not only is it a lock, it easily jibes the boom when your ready. It has a single 1/8 inche spectra line run back to the cockpit for control with a cam cleat installed at a convenient point to keep the boom locked. Bryce S/V spellbinder H410
Dutchman Boom Break!
There is also the Dutchman Boom Break. http://images.sailnet.com/dutchman/boombrake/bbindex.htm
There is also the Dutchman Boom Break. http://images.sailnet.com/dutchman/boombrake/bbindex.htm
Single line preventer
A picture is worth 1000 words, as they say. Although not in use, the system is shown well in this picture. The line going back to the cockpit, coming from the side where the boom is, makes 4 or 5 turns around the winch and the rest of the line (5-10 ft) is left loose before it returns to the bow block. This single line preventer keeps the boom out but, when an accidental jibe occurs, it acts as a boom break. I don't recommend to cleat the preventer line because it may create very high forces on the boom. In fact the line and the blocks in my boat's system are relatively small to make sure they break before the boom. The preventer can also be used to speed up jibing or keeping still the boom in light winds. I have used this preventer in my Beneteau 361 for more than a year and have had no problems with it. In fact, it was very helpful during our trip from Florida to New England when we were broad reaching or running most of the time and it had to work several times. Of course, every time an accidentally jibe occured, we had to re-set the proper side of the line on the winch. Installing it is a one beer job once you have figure out the hardware needed.
A picture is worth 1000 words, as they say. Although not in use, the system is shown well in this picture. The line going back to the cockpit, coming from the side where the boom is, makes 4 or 5 turns around the winch and the rest of the line (5-10 ft) is left loose before it returns to the bow block. This single line preventer keeps the boom out but, when an accidental jibe occurs, it acts as a boom break. I don't recommend to cleat the preventer line because it may create very high forces on the boom. In fact the line and the blocks in my boat's system are relatively small to make sure they break before the boom. The preventer can also be used to speed up jibing or keeping still the boom in light winds. I have used this preventer in my Beneteau 361 for more than a year and have had no problems with it. In fact, it was very helpful during our trip from Florida to New England when we were broad reaching or running most of the time and it had to work several times. Of course, every time an accidentally jibe occured, we had to re-set the proper side of the line on the winch. Installing it is a one beer job once you have figure out the hardware needed.
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