I'm having some trouble trimming the headsails on my '78 O'22 (masthead), especially the genoa, that I can't quite figure out. The problem is that often the luff of the sail backwinds (puffs out to windward, while the rest of the sail has a nice shape. The sailes are a hank-on 135% genoa and a 100% jib. The tell tails usually look OK, that is they are streaming back on both sides or the windward telltale lifts occasionally. I don't think the puffy luff is optimal and it only seems to go away if the sail is sheeted in REALLY tight. Sheeting in very hard also makes the telltales on both sides stream back. Coming into or falling off the wind doesn't seem to have much effect either way. So what's going on here? Does the reverse luff reduce performance? Maybe an issue of having to tighten the hayhard or headstay? (I think these are both pretty tight now.) Is this just a symptom of having a stationary lead block for the sheets (factory original, no adjustable tracks)? Thanks, Brad O'22 s/v Little Oob Port Jefferson, NY
What's going on here?
- Thread starter Brad Arrington
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Brad: As I read your message I wasn't sure what was happening - until I got to the last sentence, which says you have stationary leads. Part of the problem is that the fairleads are not adjustable. The fairleads are the most important sail trim control for the jib as they control all the elements of sail trim, which are draft position, draft depth, twist and angle of attack. I think that if you installed a short track you'd see an improvement in performance.
next time out
Try playing around with the leads for the sheet - just tie a loose loop around it with another line so you can bring it farther forward or aft of the fixed fairlead. I suspect that leading the sheet forward of where it is now will help some.
Try playing around with the leads for the sheet - just tie a loose loop around it with another line so you can bring it farther forward or aft of the fixed fairlead. I suspect that leading the sheet forward of where it is now will help some.
Track location?
Thanks. I was afraid it would require adding a track vs. making an adjustment. I didn't want to add a track just yet. Probably a good project to do over the winter when I plan on adding a furler. What's the prefered location for placing sail tracks, and what is considered "short" length?
Thanks. I was afraid it would require adding a track vs. making an adjustment. I didn't want to add a track just yet. Probably a good project to do over the winter when I plan on adding a furler. What's the prefered location for placing sail tracks, and what is considered "short" length?
First off
you need to make sure the sail is in good enough shape that its problems are not inherent. If it is 'blown out' then no lead adjustment will correct the problem. I suspect Don's suggestion of "short track" would be about 18" to 24", but you want to make sure you locate it in a position that will cover all possible leads for that sail. And you want the sail to be in good shape so that you can tell where the leads should go on various points of sail - track is wasted if it is not in a location that will be used.
you need to make sure the sail is in good enough shape that its problems are not inherent. If it is 'blown out' then no lead adjustment will correct the problem. I suspect Don's suggestion of "short track" would be about 18" to 24", but you want to make sure you locate it in a position that will cover all possible leads for that sail. And you want the sail to be in good shape so that you can tell where the leads should go on various points of sail - track is wasted if it is not in a location that will be used.
watch how tight you sheet
In addition to what has been said, watch how tightly you try to trim this boat. Sailed the heck out of the same boat for several years. I found that, while the telltales would show the headsail drawing nicely, speed would drop and leeway would radically increase when I tried to sheet very tightly. Thus, distance made good really didn't improve, or worsened. My best practice was to ease off a bit and really keep the boat footing, tacking through about 120 degrees ... I just accepted the fact that she wasn't going to point well and enjoyed her close reaching capabilities. Don's the expert here, but I think that perhaps your luff problem is a somewhat blown out sail with a very round entry. So on the leading edge, it's backwinded, but by the time you get back to the telltales the angle of attack is correct. Don? Tom Monroe Carlyle Lake
In addition to what has been said, watch how tightly you try to trim this boat. Sailed the heck out of the same boat for several years. I found that, while the telltales would show the headsail drawing nicely, speed would drop and leeway would radically increase when I tried to sheet very tightly. Thus, distance made good really didn't improve, or worsened. My best practice was to ease off a bit and really keep the boat footing, tacking through about 120 degrees ... I just accepted the fact that she wasn't going to point well and enjoyed her close reaching capabilities. Don's the expert here, but I think that perhaps your luff problem is a somewhat blown out sail with a very round entry. So on the leading edge, it's backwinded, but by the time you get back to the telltales the angle of attack is correct. Don? Tom Monroe Carlyle Lake
- Jan 22, 2008
- 519
jib lead track position
Before you install anything, take a pencil and draw a ruler line on your deck that denotes a 9 degree angle from the stem head. Draw another line that denotes a 12 degree angle from the stemhead. Next with your head sail up mark an X on the first line where the miter seam (diagonal) of your headsail would theoretically intersect your line. Do this with the second line as well. The next time you are sailing, pull the jibsheet down (by hand if you can) to each X where the block would be if you installed it there, and note your performance using a gps for speed, also note angle of heel. You will need to trim your main to just take out the luff. This is your near optimum performance on this point of sail. Depending on the type of boat you have, the X on the 9 degree line, is likely the one that shows best performance close hauled and the line on the 12 degree line shows best performance on a broad reach, but experimentation on your boat is the only way to make sure. You may have to go out as far as an 18 degree line if you have an older (non racing) hull. Now comes the tricky part! Acquire jib tracks that allow you to move the the block to where the mitre angle intersects the deck as far back as you can go, from the X on the outer 12 degree line. Lets say, for sake of description that the X is about 14 inches forward of the back of your cabin deck where you plan to mount the jib track. You acquire a jib track that is only 20 inches long, so the furthest back from the x that you can go on this line is half of that, (10 inches) Mark that spot on the 12 degree line at 10 inches behind the X. On the inner line, mark an X 10 inches forward of the X on this 9 degree line and draw a NEW line between the furthest mark forward on the 9 degree line, and the furthest mark back on the outer 12 degree line. This is the line on which you want to mount your 20" inch jib track. The performance this will give you is as a result of moving the block forward, tightening the leech and closing the slot in upwind sailing, and opening the slot and tightning the foot while reaching. Once your jib track is mounted and you have adjust your jib block to your conditons, and are pointing as close as you can, ease your main from fully hardened to where it just stops luffing. Now point your boat just slightly more off the wind than this near optimum configuration and you will be at your maximum speed. Watch your gps for confirmation! See diagram to help with the wordy explanation.
Before you install anything, take a pencil and draw a ruler line on your deck that denotes a 9 degree angle from the stem head. Draw another line that denotes a 12 degree angle from the stemhead. Next with your head sail up mark an X on the first line where the miter seam (diagonal) of your headsail would theoretically intersect your line. Do this with the second line as well. The next time you are sailing, pull the jibsheet down (by hand if you can) to each X where the block would be if you installed it there, and note your performance using a gps for speed, also note angle of heel. You will need to trim your main to just take out the luff. This is your near optimum performance on this point of sail. Depending on the type of boat you have, the X on the 9 degree line, is likely the one that shows best performance close hauled and the line on the 12 degree line shows best performance on a broad reach, but experimentation on your boat is the only way to make sure. You may have to go out as far as an 18 degree line if you have an older (non racing) hull. Now comes the tricky part! Acquire jib tracks that allow you to move the the block to where the mitre angle intersects the deck as far back as you can go, from the X on the outer 12 degree line. Lets say, for sake of description that the X is about 14 inches forward of the back of your cabin deck where you plan to mount the jib track. You acquire a jib track that is only 20 inches long, so the furthest back from the x that you can go on this line is half of that, (10 inches) Mark that spot on the 12 degree line at 10 inches behind the X. On the inner line, mark an X 10 inches forward of the X on this 9 degree line and draw a NEW line between the furthest mark forward on the 9 degree line, and the furthest mark back on the outer 12 degree line. This is the line on which you want to mount your 20" inch jib track. The performance this will give you is as a result of moving the block forward, tightening the leech and closing the slot in upwind sailing, and opening the slot and tightning the foot while reaching. Once your jib track is mounted and you have adjust your jib block to your conditons, and are pointing as close as you can, ease your main from fully hardened to where it just stops luffing. Now point your boat just slightly more off the wind than this near optimum configuration and you will be at your maximum speed. Watch your gps for confirmation! See diagram to help with the wordy explanation.
Whaaa?
Roger, Need more pictures. I want to understand, really I do. How about a side view? Would that provide more information? Please esplain this mitre seam diagonal thing. Also, how do you know how long the track should be. Seen a picture of a big Swan (70 something)and the jib car track was only two feet at the most, but it was a deck sweeper. I assume a yankee jib would need more track length to effect the same change. Yes/No? Thanks
Roger, Need more pictures. I want to understand, really I do. How about a side view? Would that provide more information? Please esplain this mitre seam diagonal thing. Also, how do you know how long the track should be. Seen a picture of a big Swan (70 something)and the jib car track was only two feet at the most, but it was a deck sweeper. I assume a yankee jib would need more track length to effect the same change. Yes/No? Thanks
- Jan 22, 2008
- 519
sorry I confused you, let me try to clarify
If you look at your jib while it is hoisted, you will see a seam line that runs diagonally from the mid luff point to the clew where your jib sheets attach. If you continue this line with your jib sheet, that is the imaginary line I am talking about. Where it intersects the deck is the ideal average position for the middle of the jib lead track from a profile prespective. Now switch to a birds eye view of your boat from the top of the mast. From the stemhead draw two lines, one 9 degrees from the centreline, the other 12 degrees from the centreline. Your track can be any length (I don't know what size track would be ideal...I just picked a random number) but let us say that where your imaginary seam line intersects the deck is about oh... 15 inches forward of any obstacle that would prevent it from ending any further back. I used the back edge of the cabin in my previous example. So lets say in this example, you only can go back 15 inches from your ideal average position, so a track 30 inches long would cover as much room to move forward as you have to move the jib block back along the track. I assume you understand the two 9 and 12 degree position lines, so I won't attempt to clarify that further. I have a scan of two pictures that shows this in a book I have and include it with this post. For this older boat described in the book, the ideal position for the jib track was on an 18 degree line, but more recent information for modern hulls suggest a line between 9 and 12 degrees from centerline. There was a recent article on this in a recent sailing magazine. Hope this helps.
If you look at your jib while it is hoisted, you will see a seam line that runs diagonally from the mid luff point to the clew where your jib sheets attach. If you continue this line with your jib sheet, that is the imaginary line I am talking about. Where it intersects the deck is the ideal average position for the middle of the jib lead track from a profile prespective. Now switch to a birds eye view of your boat from the top of the mast. From the stemhead draw two lines, one 9 degrees from the centreline, the other 12 degrees from the centreline. Your track can be any length (I don't know what size track would be ideal...I just picked a random number) but let us say that where your imaginary seam line intersects the deck is about oh... 15 inches forward of any obstacle that would prevent it from ending any further back. I used the back edge of the cabin in my previous example. So lets say in this example, you only can go back 15 inches from your ideal average position, so a track 30 inches long would cover as much room to move forward as you have to move the jib block back along the track. I assume you understand the two 9 and 12 degree position lines, so I won't attempt to clarify that further. I have a scan of two pictures that shows this in a book I have and include it with this post. For this older boat described in the book, the ideal position for the jib track was on an 18 degree line, but more recent information for modern hulls suggest a line between 9 and 12 degrees from centerline. There was a recent article on this in a recent sailing magazine. Hope this helps.
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