Hello guys and gals! Below is a discussion from my web site, Skip's South Coast Yachts. An individual there was wondering why his boat was set up in a particular way. And I went on to explain to him that his boat was set up so that his mast rake could be adjusted. Could you guys read these messages? After it is all said and done, I explained that aft mast rake creates a larger pocket in the sail....And more pocket creates more power to a point. And less aft mast rake creates a flatter sail. A flatter sail depowers the main and therefore creates less power. Take a look at my argument and Vince's argument and tell me what you guys think! Skipperofthebaybee...Skipper From Ohio, (Eric Stanson) Hi Giorgio, This device is the first thing I noticed when I looked at your picture of your boat. But I kept quiet thinking that if I did not say anything, you would not bring it up. hehehe. But here we are any way discussing it. Well, it was my first impulse to comment on it. But I held back. The previous owner was trying to mimic a system found usually on bigger and or more elaborate yachts (usually high performance and or racing yachts). It is a mast rake adjuster. A mast rake adjuster is used to put bend in the mast. The reason you want bend in a mast is to put more pocket in your main. And the reason you want more pocket in the main is so that you achieve more power out of the wind. For example, a flat wing has much less lift than a curved one. The thing that got my attention though is that he did not finish his work He was only half done with the job. In order to place bend in the mast, you first have to have an additional forestay on the boat. (A baby forestay,,,,usually runs from mid deck to aprox. 3/4 of the way up the mast) When you pull on the back stay adjustments, you will then bend the portion of the mast that is above this cable creating a bend that goes abaft. Honestly, on your boat, this is really unneeded. First, your mast is not tapered to allow for a safe bend. You will only stress the mast at its weakest points. Also, the South Coast 22 has a very short bow. This is a poor arrangement for an additional forestay and will actually get in the way of your head sails. Here is my recommendation. Yes, I would keep it. Although it is not doing what it was intended to do, it still is a great tool for tensioning you back stay and forestay all at the same time. All you have to do is set your forestay so your mast rake is aprox 5-7 degrees abaft (Angled backwards) and then pull on your adjusters to take up the slack. Then make sure your side stays are adjusted correctly as well. If you choose, you can place a stop or a stop knot in the line past the cleat. This way, a child or guest will not accidentally release the line. But I would not place a second line as a back up. There really is no need if you place a stop in the line. There is very little pressure on the back stay even in the worst of conditions. The only time you put stress on the back stay is when you head down wind. All other times, the force is placed on the forward stay and a combination of the side stays. Your Friend, "The Skipper" Now tell me this! Where else on the net will you find advice like that??? That will be 25 cents please! From: mariner (manager) Sent: 9/18/2002 9:48 PM Hey.....sob..sob.., My SC22 has no numbers in the fiber glass on the stern......mine has numbers on the plate at the rear of the cot pit.... Am I to understand these were put on at the whim of a mentally and socially challenged individual and mean nothing to anyone but him.. Was not my boat built in 1971??? and if it was why are there no mandated numbers on the stern?. Have I traded my existense on a pocket full of mumbo jumbo such as promises and lies? ( figure out what song that came out of and you will be as dated as I.). Next thing you know they will ban dwarf tossing and we will no longer be able to buy Cuban cigars...........! You know I lost my train of thought several lines back but I still wonder if mine was the 78th SC22 built. Friend to ya all... Mariner Chuck. From: Skipper (Manager) Sent: 9/18/2002 10:02 PM Hey Mariner! Man, You are not going to believe this! But after your post, I realized that you and I have one more thing in common! I love to play dwarf toss too!!!!!!!!!!! Man! Every Saturday night I meet with a local chapter here in Logan, Ohio to play a few rounds of dwarf toss. It's great! The problem is that we are "short" a few dwarfs! We need 10 to make it any fun but all we have is 7. Do you guys up north have any dwarfs you can spare? Get back with me when you can. I along with the other guys in the club are anxiously waiting for your reply! Hey Chuck! I have a secret I will tell you concerning my success as a dwarf tosser. I have a winning streak now of 22 games. The reason for my success is my technique of putting a right hand spin on my dwarf. The dwarfs hate it but man,,,,I hit my target every time. Talk to you soon Mariner! Your Buddy Skipper (Friend to all who like to dwarf toss on a Saturday night) From: giorgio Sent: 9/18/2002 10:03 PM But Skipper, There is a second forestay. I thought that this was for my "staysail" This stay comes to the center of the foredeck. (approx) See it there, coming down to the center of the fore deck? and he has added a "pulpit extension" to move the forward stay and additional foot forward of the original location. All of this remains a mystery to me, but maybe with help for you all, (y'all) I will eventually figure it all out, whether I ever use it or not. Giorgio From: Skipper (Manager) Sent: 9/18/2002 10:15 PM Oh, well then I take back the part about how he was not finished. He is indeed finished and he had accomplished his task. Still your mast is not made for bending but if you want to use this, I am sure it will work. Here is what you do. Fist go back and read my last statement concerning this arrangement. It will give you an idea of what it is for. 1. Attach the small forestay leaving the forward most say unattached. 2. Adjust it so that your mast sits back at about 5 degrees or so 3. Adjust your side stays to make them both snug (snug enough so that the leeward side does not go floppy while sailing. 4. pull back on the adjuster to create aprox. a 3-5 percent aft bend. 5. attach the forward most forestay (Make it snug enough but not so snug that you take pressure of the baby forestay. You want the baby stay to take the load in this case. (Realize that you only want to create bend in medium to low wind situations. In high winds, you want to take the bend out of the mast to flatten the sail. In order to do this, you just leave the baby forestay loose but not so loose that it dangles all over the place) Personally, unless you are racing, there is no need for this arrangement. Skipper That will be an additional 25 cents please! Now where else on the web are you going to find advice like that? From: Skipper (Manager) Sent: 9/18/2002 10:22 PM Skipper's South Coast Yachts -------------------------------------------------------------------------------- Managed by knowledgeable sailors with over 50 years of experience between the two! Skipper (Eric V. Stanson) and Sub Driver (Joseph Klep) From: giorgio Sent: 9/18/2002 10:29 PM Skipper, Nowhere that I know of. I have no plans to use any of that "extra" stuff for a long, long, time. Just curious about it all. Thanks for the "enlightenment:" about it all! Maybe one day, I will use some of it. It is interesting to know about the theory behind it all though! Thanks again, Giorgio From: giorgio Sent: 9/18/2002 10:44 PM Mariner, You must be suffering from "Sid Response Syndrome" AKA "SRS" I, too, have suffered from this at least three times in the recent past, since signing up on this message board. I think that it should pass soon. Take three beverages of choice, and then get a good night's sleep! After all, Tomorrow is another Day! Giorgio From: Vince Sent: 4/18/2003 8:09 AM Hi Skipper, I was re-reading messages and came around the message of yours about prebend. prebend and backstay bend will push the middle of the sail forward relative to the head (tip of mast) and the clew (where the boom and mast connect). This will cause flattening of the mainsail and is great in heavy air, not light! It will pull the excess bag in the sail to move roughly forward and the mast tip back creating a flatter sail. BY THE way, this is used for going UPWIND MOSTLY!! INTO the wind! Downwind is almost the opposite! In lower winds you want some bag for rounder chord depth, like a big fat airplane wing. In higher winds flat like a fast flat fighter wing. Just be gentle when adjusting. Too fat is slow and too much flat and you can't get the wind to go a-round the back of the sail and it will stall. Also some mainsails aren't cut with big middle girth to pull out so each boat is just a li'l bit different. In the racing world it is said "flat is fast!" By coincidence it relates to TWO things! When you have a flat main, compared to the wind speed, you will also have less sideways drag! So the boat will stand up better in the wind with the SAME properly trimmed (sheeted) sail. Now I am going to add something! When the mast tip is moved back, the forestay is tightened too! You always need a little bend in that to make the the jib behave itself and allow you to steer the boat into the wind. So watch your back stay tension for that too. AND finally, the halyards have an influence on the position of the bag in the sail. When sails are up and wind is blowing, you generally want the draft, the thickest chord depth or belly, to be about 50% back on the mainsail and 40% back on the jib or Genoa. The tighter you pull on the halyards the farther FORWARD the draft goes. So if you can't seem to get the draft to come back on the jib by loosening the halyard, you may have too much backstay pressure which is pulling the forestay, connected to the front of the sail, too tight! : ) with wind in his ears, Vince of N -------------------------------------------------------------------------------- Add photos to your e-mail with MSN 8. Get 2 months FREE*. Reply Recommend Delete Message 19 of 19 in Discussion From: Skipper (Manager) Sent: 4/18/2003 8:48 AM Hi Vince of the North Pole! Hey, are you sure about that? I mean are you sure your sure? Are you absolutely positively sure your sure? Listen to my argument. Take two straws. Put them together just as a mast and a boom. Then tape a paper towel to them just as a sail would fit on a real sail boat. It starts out some what flat. Of course a real main sail has a pocket built into it depending on how old and blown out it is. Now, while holding down on the base of the straw that holds the sail like model, take your other hand and bend the top of the fake mast model back. Even go so far as to exaggerate this situation. You will find that you will end up with a napkin that has a huge pocket in it....Not a flatter napkin at all! I have always been told and have read that bending the mast back creates a pocket in the main sail. Of course I may have misunderstood. If you think I am wrong, I want to hear back from you. Please reply to tell me what you think! Your Pal, Skipper of the South Zambula Bula Tribe!
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David Stone
Vince is right...
After 20 years of racing experience on boats from 15 feet to 45 feet, I really, really know for sure that tensioning the backstay adjuster & BENDING the mast will increase headstay tension (helping you to point higher) & it will depower the main by flattening it. The center of the mast will pull the sailcloth forward with it. That makes less material for the "pocket". It could also loosen the halyard allowing wrinkles to form on the luff. These wrinkles run from the center of the mast toward the clew. At the same time, the deepest part of the sail (max draft) will move aft. This may cause the sail to look fuller (big pocket). Its very bad for pointing, speed & heel. If you now tension the halyard to remove most or all of the luff wrinkles, you will at the same time be moving tha max draft position forward in the sail. Max draft should be about 40 to 50% aft of the mast. This opens the leech so the boat can stand up & the sail should be very flat. If you can't pull all the wrinkles out with the halyard, the mast is bent too much FOR THAT SAIL. Get a sail cut for the amount of bend or ease the backstay adjuster. You don't need an inner forestay (baby stay?) unless you run a staysail or the mast needs the support. The old Buccaneers needed the babystay to keep the mast in one piece when the wind was up. You aren't raking the mast all that much. The lower shrouds (assuming there are four) hold the mast in position. The backstay adjuster pulls the mast aft until the fore lower gets tight & prevents the center of the mast from moving further aft. The masthead continues aft bending the mast. Use the aft lower to limit the amount of bend. Otherwise, the mast will pump forward & aft & eventually fail. We're talking mast bend here. Mast rake would require all the shrouds to be reset as the rake changes. Mast rake is the amount of forward or aftward "lean" the mast has. Hope this helps
After 20 years of racing experience on boats from 15 feet to 45 feet, I really, really know for sure that tensioning the backstay adjuster & BENDING the mast will increase headstay tension (helping you to point higher) & it will depower the main by flattening it. The center of the mast will pull the sailcloth forward with it. That makes less material for the "pocket". It could also loosen the halyard allowing wrinkles to form on the luff. These wrinkles run from the center of the mast toward the clew. At the same time, the deepest part of the sail (max draft) will move aft. This may cause the sail to look fuller (big pocket). Its very bad for pointing, speed & heel. If you now tension the halyard to remove most or all of the luff wrinkles, you will at the same time be moving tha max draft position forward in the sail. Max draft should be about 40 to 50% aft of the mast. This opens the leech so the boat can stand up & the sail should be very flat. If you can't pull all the wrinkles out with the halyard, the mast is bent too much FOR THAT SAIL. Get a sail cut for the amount of bend or ease the backstay adjuster. You don't need an inner forestay (baby stay?) unless you run a staysail or the mast needs the support. The old Buccaneers needed the babystay to keep the mast in one piece when the wind was up. You aren't raking the mast all that much. The lower shrouds (assuming there are four) hold the mast in position. The backstay adjuster pulls the mast aft until the fore lower gets tight & prevents the center of the mast from moving further aft. The masthead continues aft bending the mast. Use the aft lower to limit the amount of bend. Otherwise, the mast will pump forward & aft & eventually fail. We're talking mast bend here. Mast rake would require all the shrouds to be reset as the rake changes. Mast rake is the amount of forward or aftward "lean" the mast has. Hope this helps
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Terry
Hi Eric, from all that I've read on the topic...
to me Vince is the most accurate. Think of it like shifting gears in your car; fat sail low gear, flat sail high gear. Also, you do not need an inner stay to control mast bend. The stick maker can tell you how much bend it will handle without causing fatigue. Your outhaul is an important, but often overlooked, adjustment in this process,too. Terry
to me Vince is the most accurate. Think of it like shifting gears in your car; fat sail low gear, flat sail high gear. Also, you do not need an inner stay to control mast bend. The stick maker can tell you how much bend it will handle without causing fatigue. Your outhaul is an important, but often overlooked, adjustment in this process,too. Terry
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Robert Polk
Confusion between rake and bend
Raking a mast means to rotate the rig forward or aft with the mast straight. It does not affect flatness of the main. The main reason to add or remove rake is to move the center of effort aft or forward and properly balane the helm of the boat to waether so that rudder corrections are minimized.
Raking a mast means to rotate the rig forward or aft with the mast straight. It does not affect flatness of the main. The main reason to add or remove rake is to move the center of effort aft or forward and properly balane the helm of the boat to waether so that rudder corrections are minimized.
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Skipper (Eric)
Thank you Robert! I just learned something!
Hi Robert! Shoot, you are correct and I stand corrected. I ment mast bend not rake! Woops. Well, put bend in the place of all the placed I put Rake and give me your opinion if you could! Thank you for the correction. I just learned something thanx to you! And let me tell ya, it is hard for me to learn. My wife has been trying to learm me with a great big stick for years and years and it hasn't worked yet! Your Pal, Skipper
Hi Robert! Shoot, you are correct and I stand corrected. I ment mast bend not rake! Woops. Well, put bend in the place of all the placed I put Rake and give me your opinion if you could! Thank you for the correction. I just learned something thanx to you! And let me tell ya, it is hard for me to learn. My wife has been trying to learm me with a great big stick for years and years and it hasn't worked yet! Your Pal, Skipper
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Skipper (Eric)
Instant mast bend
Now Terry, You are not supposed to agree with the enemy! Hahahaha. O.k. I was wrong. I think I understand the whole thing now. I never had a boat that I could control mast bend before. I of course had boats that I could control the sail shape via down haul, out haul, travelor etc. I have had a catamaran for over 10 years. Those are great boats to learn on. Any adjustment gives you almost instant results! A funny story from Skipper: A buddy of mine had a Catalena 22. When he got it, the mast was strait. But one day he accidentally drove over the mast. (Instant mast bend) He figured oh well, Ya can't chage what damage has been done. So, he put it up on his boat any way. Hahahaha. That entire summer I joked about his bent mast. It was bent to one side rather than bent abaft as you would expect. Haahahaha. He said it was specially bent for performance. Funny thing is...He sailed a whole lot better on one tack rather than the other! Hehehehe Your Friendly Hunter 27 owner, Skipper
Now Terry, You are not supposed to agree with the enemy! Hahahaha. O.k. I was wrong. I think I understand the whole thing now. I never had a boat that I could control mast bend before. I of course had boats that I could control the sail shape via down haul, out haul, travelor etc. I have had a catamaran for over 10 years. Those are great boats to learn on. Any adjustment gives you almost instant results! A funny story from Skipper: A buddy of mine had a Catalena 22. When he got it, the mast was strait. But one day he accidentally drove over the mast. (Instant mast bend) He figured oh well, Ya can't chage what damage has been done. So, he put it up on his boat any way. Hahahaha. That entire summer I joked about his bent mast. It was bent to one side rather than bent abaft as you would expect. Haahahaha. He said it was specially bent for performance. Funny thing is...He sailed a whole lot better on one tack rather than the other! Hehehehe Your Friendly Hunter 27 owner, Skipper
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S. Sauer
Sail Trim Guides
In general, bending the mast is intended to flatten the sail and depower the boat as wind speed increases. More halyard tension will generally pull the draft forward for a more powerful 'wing' or airfoil shape. Less halyard tension results in the midpoint of the draft moving aft to 45-50% of the width of the sail for higher pointing. Also, it isn't necessary to have a baby stay on a typical Hunter double spreader mast head B&R rig because the mast will stay in column and bend uniformly due to the 'X' bracing between both sets of spreaders. The newer ractional rigs act differently due to the location of the headstay, and a babystay may be necessary to control bend. If you want to read a serries of expert discussions on all types of wind and sail trim combinations, for racing as well as cruising, I would recommend two paperback books: The Best of SAIL Trim, edited by Charles Mason (paperback edition 1989) and The New Book of SAIL Trim, edited by Keith Textor, published 1995. Both books are a compilation of articles originally published in SAIL Magazine.
In general, bending the mast is intended to flatten the sail and depower the boat as wind speed increases. More halyard tension will generally pull the draft forward for a more powerful 'wing' or airfoil shape. Less halyard tension results in the midpoint of the draft moving aft to 45-50% of the width of the sail for higher pointing. Also, it isn't necessary to have a baby stay on a typical Hunter double spreader mast head B&R rig because the mast will stay in column and bend uniformly due to the 'X' bracing between both sets of spreaders. The newer ractional rigs act differently due to the location of the headstay, and a babystay may be necessary to control bend. If you want to read a serries of expert discussions on all types of wind and sail trim combinations, for racing as well as cruising, I would recommend two paperback books: The Best of SAIL Trim, edited by Charles Mason (paperback edition 1989) and The New Book of SAIL Trim, edited by Keith Textor, published 1995. Both books are a compilation of articles originally published in SAIL Magazine.
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Skipper (Eric)
This is what I understand...Rake and Bend
Rake not mast bend, moves the mast aft. It makes the sails move aft too and by moving the center of side force to move aft toward the rudder gives a different helm, many times a weather helm, and more of an ability to point to weather, if done right. Putting in prebend changes sail shape (draft or chord depth) without necessarily moving the mast tip forward or aft, but allows the backstay to more easily bend the mast with backstay tension. Mast bend with backstay controls move the forces aft or foreward, but can ALSO be used to change draft or sail shape by changing the mast bend. When going upwind tighten the backstay tension, to the wind speed, and going downwind release the backstay, within reason not completely, to make the sails fatten and forces move forward. Mostly the rake moves the tip forward or aft, compression causes bend in the mast that changes sail shape AND will move the mast tip forward or aft. The amount of forward or aft motion by the backstay is also influenced by how much slop you have in the forestay. When the bend happens by shortening the backstay and compressing the mast to bow the middle forward, the forestay remains the same length (although it still has sag) so the now shorter mast due to compression and bend will move the tip aft, but not as much as rake. There once was a boat I know of that was made that raced in MORC, Midget Ocean Racing Class, a Lindenberg 26 footer that forced changes in many racing rules because it had rams underneath the deck that changed ALL stays fore, aft, and both sides to move the tip, the bend and compressions all over while underway!! Even the babystay that goes up about halfway up the mast from the front deck! BY the way, adjustment is needed for your jib halyard with the movements of the mast and backstay!! If the tip does get moved aft your halyard will be tensioned along wth the forestay! When you release the bend in the mast it'll straighten too and make the halyards change tension. Jibs must have sag to work efficiently. By forestay tension AND by halyard tensions. Too flat is hard to sail too!!! : ) Skipper of the Baybee, Blue Bird, The Marina, X 2 Sea, The Victor, The Marisa and My Dingy
Rake not mast bend, moves the mast aft. It makes the sails move aft too and by moving the center of side force to move aft toward the rudder gives a different helm, many times a weather helm, and more of an ability to point to weather, if done right. Putting in prebend changes sail shape (draft or chord depth) without necessarily moving the mast tip forward or aft, but allows the backstay to more easily bend the mast with backstay tension. Mast bend with backstay controls move the forces aft or foreward, but can ALSO be used to change draft or sail shape by changing the mast bend. When going upwind tighten the backstay tension, to the wind speed, and going downwind release the backstay, within reason not completely, to make the sails fatten and forces move forward. Mostly the rake moves the tip forward or aft, compression causes bend in the mast that changes sail shape AND will move the mast tip forward or aft. The amount of forward or aft motion by the backstay is also influenced by how much slop you have in the forestay. When the bend happens by shortening the backstay and compressing the mast to bow the middle forward, the forestay remains the same length (although it still has sag) so the now shorter mast due to compression and bend will move the tip aft, but not as much as rake. There once was a boat I know of that was made that raced in MORC, Midget Ocean Racing Class, a Lindenberg 26 footer that forced changes in many racing rules because it had rams underneath the deck that changed ALL stays fore, aft, and both sides to move the tip, the bend and compressions all over while underway!! Even the babystay that goes up about halfway up the mast from the front deck! BY the way, adjustment is needed for your jib halyard with the movements of the mast and backstay!! If the tip does get moved aft your halyard will be tensioned along wth the forestay! When you release the bend in the mast it'll straighten too and make the halyards change tension. Jibs must have sag to work efficiently. By forestay tension AND by halyard tensions. Too flat is hard to sail too!!! : ) Skipper of the Baybee, Blue Bird, The Marina, X 2 Sea, The Victor, The Marisa and My Dingy
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Skipper (Eric)
Sauer, could you explain what you said once more?
Hi Sauer, Explain in more detail about pulling harder on the halyard. If I understand you correctly, you are saying to pull on it while the mast is bent (to a flat sail) moves the pocket that remains forward? Skipper
Hi Sauer, Explain in more detail about pulling harder on the halyard. If I understand you correctly, you are saying to pull on it while the mast is bent (to a flat sail) moves the pocket that remains forward? Skipper
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