How much rake is normal for this boat? I bought the boat last year and the headstay/furlex furler that came with the boat is not adjustable. The boat developes pretty strong helm above 15kts and I feel its because the of the rake. The stay probably stretched a bit since '88 and I might have to shorten the stay to get the mast more vertical.
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Gregory Stebbins
Oboy, here we go
Steve, Look up a post called 23 rigging questions and start from there. There's been a long running discussion on this issue. 1st know which mast you've got...
Steve, Look up a post called 23 rigging questions and start from there. There's been a long running discussion on this issue. 1st know which mast you've got...
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Russell
Hire a rigger
I was having the same sort of problems on my 240. At Crazy Dave's advice, I had a rigger come and look my boat over. His findings, Too much rake at 13 inches(dealer said it was right), and some other minor things like rusted pins. It cost me 60 bucks and the boat sails great. It definatly made a big difference. Russell s/v Sumer Luvin'
I was having the same sort of problems on my 240. At Crazy Dave's advice, I had a rigger come and look my boat over. His findings, Too much rake at 13 inches(dealer said it was right), and some other minor things like rusted pins. It cost me 60 bucks and the boat sails great. It definatly made a big difference. Russell s/v Sumer Luvin'
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William Davis
RE Mast Rake
Just this past weekend, I fixed the same problem with my H23. Cliff fixed me up just fine. Thanks Cliff, Here is what I did: slack up your short stays and back stay. Sight up the mast (at the track for the main sail) and note the bend. (mine was bent aft about 8") With the slack in the stays, go forward the take up the slack in your forstay. This will move the top of your mast forward and help your weather helm problem. I moved the top of mine about 7-8" forward. I have the adjustable back stay and now when its loose, the mast is pretty straight, but when I crank on the back stay, I get a nice bend. This was not hard at all, and really made the boat faster. Any Q's e-mail "Daviss@vnet.net"
Just this past weekend, I fixed the same problem with my H23. Cliff fixed me up just fine. Thanks Cliff, Here is what I did: slack up your short stays and back stay. Sight up the mast (at the track for the main sail) and note the bend. (mine was bent aft about 8") With the slack in the stays, go forward the take up the slack in your forstay. This will move the top of your mast forward and help your weather helm problem. I moved the top of mine about 7-8" forward. I have the adjustable back stay and now when its loose, the mast is pretty straight, but when I crank on the back stay, I get a nice bend. This was not hard at all, and really made the boat faster. Any Q's e-mail "Daviss@vnet.net"
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Jim Malcolm
How to Measure Rake
How do you measure 8" of mast rake? I assume this is the difference between absolute vertical between bottom of mast and top of mast measured at the edge, e.g., back, but how can you tell that is 8" vice 6"?
How do you measure 8" of mast rake? I assume this is the difference between absolute vertical between bottom of mast and top of mast measured at the edge, e.g., back, but how can you tell that is 8" vice 6"?
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Gregory Stebbins
Measure Mast Rake
Jim, Hang a small weight from main halyard. Lower to just above deck level. See how far center of weight hangs from trailing edge of mast. That's your rake. Greg 23' Faster
Jim, Hang a small weight from main halyard. Lower to just above deck level. See how far center of weight hangs from trailing edge of mast. That's your rake. Greg 23' Faster
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MikeY
Mast bend
I'm surprised the mast will bend that much, seeing it's aluminum ? It seems less rake = less weather helm but more heel ?
I'm surprised the mast will bend that much, seeing it's aluminum ? It seems less rake = less weather helm but more heel ?
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Gregory Stebbins
MikeY
Alloys of Aluminum are legion. Everything from almost as soft as lead to hard as steel and brittle as glass. The particular alloy is flexible and the mast shape both in cross section and profile are fairly sophisticated. It's a case where many man-made complex and interrelated elements are brought together to make a pretty good substitute for a spruce stick.
Alloys of Aluminum are legion. Everything from almost as soft as lead to hard as steel and brittle as glass. The particular alloy is flexible and the mast shape both in cross section and profile are fairly sophisticated. It's a case where many man-made complex and interrelated elements are brought together to make a pretty good substitute for a spruce stick.
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Jim Kolstoe
Rake, Weather Helm and Heel
Mikey: Rake is one of the factors in weather helm, along with sail trim and wind strength. If you ever get on a board sailer you will discover that steering is by tilting the mast forward and backward, i.e., changing the rake of the sail. What's actually happening is that you're changing the location of the center of effort relative to the center of lateral resistance. Think of a windex: push behind the pivot, it points towards you, push in front of the pivot and it turns away from you. Push at the pivot and its neutral (if it doesn't fall over). The pivot is the center of lateral resistance, your finger pushing is the center of effort. Similarly, if you let out your main sheet, the main is producing a smaller proportion of the oveall power of your sails, so the center of effort moves forward, changing its position relative to the center of lateral resistance and reducing weather helm. I've met sailors who can steer keel boats this way, and its said to be an emergency method of maintaining steering control if you lose your rudder. As for heel, well, sails develop lift (power) perpendicular to the leeward surface of the sail, at all points on the sail. Since most of the sail faces to the side of the boat, it pushes that way, on a long lever we call a mast. This is how we wash the windows, excuse me, why we heel. Jim Kolstoe
Mikey: Rake is one of the factors in weather helm, along with sail trim and wind strength. If you ever get on a board sailer you will discover that steering is by tilting the mast forward and backward, i.e., changing the rake of the sail. What's actually happening is that you're changing the location of the center of effort relative to the center of lateral resistance. Think of a windex: push behind the pivot, it points towards you, push in front of the pivot and it turns away from you. Push at the pivot and its neutral (if it doesn't fall over). The pivot is the center of lateral resistance, your finger pushing is the center of effort. Similarly, if you let out your main sheet, the main is producing a smaller proportion of the oveall power of your sails, so the center of effort moves forward, changing its position relative to the center of lateral resistance and reducing weather helm. I've met sailors who can steer keel boats this way, and its said to be an emergency method of maintaining steering control if you lose your rudder. As for heel, well, sails develop lift (power) perpendicular to the leeward surface of the sail, at all points on the sail. Since most of the sail faces to the side of the boat, it pushes that way, on a long lever we call a mast. This is how we wash the windows, excuse me, why we heel. Jim Kolstoe
Mast bend and rake
MikeY: As others have already posted, mast rake affects your helm. Mast bend allows you to change the draft of the mainsail. More bend flattens the main and moves the draft back, producing less lift. This is one of the things you can do to keep the boat on its feet when the wind starts to pick up. Less bend causes your main to be fuller, moves the draft forward and makes it a little harder to stall (luff) so you still have lift, which is useful when the wind starts to die. The closest analogy is the wing of a jet aircraft. Thin flat wing for high airspeed, thick wing (flaps etc.) for low airspeed. Good luck. Peter s/v Raven
MikeY: As others have already posted, mast rake affects your helm. Mast bend allows you to change the draft of the mainsail. More bend flattens the main and moves the draft back, producing less lift. This is one of the things you can do to keep the boat on its feet when the wind starts to pick up. Less bend causes your main to be fuller, moves the draft forward and makes it a little harder to stall (luff) so you still have lift, which is useful when the wind starts to die. The closest analogy is the wing of a jet aircraft. Thin flat wing for high airspeed, thick wing (flaps etc.) for low airspeed. Good luck. Peter s/v Raven
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