When I first got my H23 I noticed that shrouds were not real tight. I know the rig on this boat (Z-Spar mast with the taper at the top) is supposed to be real bendy with lots of tuning flexibility, but I didn't think it should be THAT bendy. I bought a Loos gauge and tightened up the rig (20% of the breaking strength of the wire or about 700 lb on both upper and lower shrouds). Now the leeward shrouds no longer go slack in the puffs, but the boat heels more and I have to pull the traveler way up and ease the mainsheet to twist the top of the mainsail. Did I tighten the uppers so much that the top of the mast doesn't bend off to leeward anymore? I read somewhere that bending the mast to leeward will reduce leech tension and open the upper portion of the sail. However, I also read somewhere else that the leeward shrouds should not go slack. What's the truth here? Peter H23 "Raven"
Lateral mast bend and mainsail trim
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Ray Bowles
Peter, I'm very interested in the responses..
to your question. I too bought a Loos gauge for my 95 H26 but didn't have the guts to go to 700+ lbs so I did 620# on the uppers and 460 on the lowers. I set the mast rake according to the Hunter manual. The shrouds settled down to 480 and 400 after 4 days of hard use. The boat points much, much better but also heels enough more that I have also slackened the main sheet. I do not have a traveler. Ray
to your question. I too bought a Loos gauge for my 95 H26 but didn't have the guts to go to 700+ lbs so I did 620# on the uppers and 460 on the lowers. I set the mast rake according to the Hunter manual. The shrouds settled down to 480 and 400 after 4 days of hard use. The boat points much, much better but also heels enough more that I have also slackened the main sheet. I do not have a traveler. Ray
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Don Guillette
Peter; Bending the mast sideways is not a trim adjustment to my way of thinking. I almost think it is dangerous.Also, you can't have the rigging so tight that the leewards have no slack. I just returned from the Catalina 30 Nationals in Santa Cruz, Ca. In one race we sailed in winds in excess of 37 knots. One of the boats was completely dismated. I don't know if what caused the failure but it was an awful sight to see. As an amatuer, who knows his limitations, I really don't want to fool with my rigging with out completely know what I'm doing.. Anyway, I have a Loos rigging gauge. I bought it after I saw my dock neighbor using one. He checked my rigging and not one wire was the same!! Before I start messing ( adjusting) with my rigging, I want to check with my rigger for the proper settings. That reminds me that I should get the info this weekend and tune the rig.
Rig tension
The shroud tension (20% of wire breaking strength) was based on recommendations I received from several owners who successfully race their H23's. That load level makes sense to me. The described load is static, with no wind in the sails. Under way in a good breeze, the load in the shrouds could easily double. Assuming the yield strength of the wire is 50% of its breaking strength (a conservative guess to allow for aging of the wire) there is still a reasonable margin of safety. I am thinking of keeping the 700 lb in the lowers (to make sure the mast remains centered in the boat) and reducing the load in the uppers to about 350 lb to allow the top of the mast to bend off to leeward. As I said originally, I am having a hard time getting the top of the mainsail to twist off. Although I know that the age of the sail may have something to do with this, I also know the mast is designed to be very bendy, hence my suspicion that the top of the mast may be designed to bend to leeward in a puff and open the leech. Here's some info on the rig. It is a 7/8 fractional rig with swept-back spreaders and an adjustable split backstay. The mast is a ZSpar that is about six feet taller than a C-22 and tapered at the top. The cross-section also appears to be smaller than a C-22. With no sail load on the rig, the rake is about 6 inches & mast bend is 1-1/2 inches. The swept-back spreaders mean that any adjustment in shroud tension also affects the forestay tension. I'm about to tear out what's left of my hair!! Thanks again for all your help. Peter H23 "Raven"
The shroud tension (20% of wire breaking strength) was based on recommendations I received from several owners who successfully race their H23's. That load level makes sense to me. The described load is static, with no wind in the sails. Under way in a good breeze, the load in the shrouds could easily double. Assuming the yield strength of the wire is 50% of its breaking strength (a conservative guess to allow for aging of the wire) there is still a reasonable margin of safety. I am thinking of keeping the 700 lb in the lowers (to make sure the mast remains centered in the boat) and reducing the load in the uppers to about 350 lb to allow the top of the mast to bend off to leeward. As I said originally, I am having a hard time getting the top of the mainsail to twist off. Although I know that the age of the sail may have something to do with this, I also know the mast is designed to be very bendy, hence my suspicion that the top of the mast may be designed to bend to leeward in a puff and open the leech. Here's some info on the rig. It is a 7/8 fractional rig with swept-back spreaders and an adjustable split backstay. The mast is a ZSpar that is about six feet taller than a C-22 and tapered at the top. The cross-section also appears to be smaller than a C-22. With no sail load on the rig, the rake is about 6 inches & mast bend is 1-1/2 inches. The swept-back spreaders mean that any adjustment in shroud tension also affects the forestay tension. I'm about to tear out what's left of my hair!! Thanks again for all your help. Peter H23 "Raven"
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Michael McCann
Mast bend
I agree with Don Guillette about a mast bending off to leward to put twist in the mainsail. I have always read that you ease the main sheet, and move the traveler to leward to induce twist in the top of the main to depower. If you do not see some slack in the leward shrouds when sailing hard to weather you are asking for trouble. I again say that the 20% settings are not absolute, and that the forward, and aft lowers do not have to be the same setting. The shrouds should only be tight enough to keep the mast straight while sailing. Use the guage to adjust each shroud the same as the opposite one. The fore, and aft stays are tensioned according to the point of sail. Read some books! Michael
I agree with Don Guillette about a mast bending off to leward to put twist in the mainsail. I have always read that you ease the main sheet, and move the traveler to leward to induce twist in the top of the main to depower. If you do not see some slack in the leward shrouds when sailing hard to weather you are asking for trouble. I again say that the 20% settings are not absolute, and that the forward, and aft lowers do not have to be the same setting. The shrouds should only be tight enough to keep the mast straight while sailing. Use the guage to adjust each shroud the same as the opposite one. The fore, and aft stays are tensioned according to the point of sail. Read some books! Michael
Response to Mike
I've read a couple of books on sail trim, and I have Don Guilette's on order. My confusion stems from the apparent discrepancy between the books and what actually happens on the water. I used to believe that easing the mainsheet and the traveler would depower the main. That is, until I was out racing once in heavy air and the other H23s blew by with their travelers pulled ALL the way up to windward and the mainsheet eased out to put the boom back on the centerline. I found out afterwards that they were using the traveler and sheet against each other to maintain the proper angle of attack on the lower 2/3 of the sail and keep it powered up. Meanwhile, the reduced tension from the eased mainsheet lessened the downward pull on the boom, which allowed it to rise and reduce leech tension. This opened the leech, twisting the sail so it could spill air off the top 1/3 and reduce heel. It works, because in conditions when others are reefing their mains, I can still carry full sail. This is really handy on the downwind legs. Even though this method works, tacking is a pain, and I suspect something is not right. That's when I recalled that the boat sailed better when the shrouds weren't as tight as they are now. I know from reading up on boat trim that allowing the masthead to bend off to leeward will open the leech. I also know that the H23 rig is very bendy. As described earlier it's a 7/8 fractional rig with approx. 5/8 of the mast above the swept-back spreaders. The mast section above the forestay is tapered. Compared to other boats of the same length, my mast is slimmer, the spreaders are at the same height or slightly lower, my forestay is about the same height as their masthead, and I have four or five feet more mast above the forestay. I will post a picture in the photo forum so you can see what I'm talking about. Those features (and experience with the adjustable backstay) tell me that the top of this mast was made to bend. The question is this...is lateral bend a part of the tuning characteristics of THIS rig? Assuming lateral mast bend is not part of the equation, then it seems that the vang is the answer to controlling leech tension. That way, the downward pull of the mainsheet does not affect the leech, i.e. the boom "floats". However, for that to happen, doesn't the vang have to be pulling down harder than the mainsheet was before? I need a beer. Peter H23 "Raven"
I've read a couple of books on sail trim, and I have Don Guilette's on order. My confusion stems from the apparent discrepancy between the books and what actually happens on the water. I used to believe that easing the mainsheet and the traveler would depower the main. That is, until I was out racing once in heavy air and the other H23s blew by with their travelers pulled ALL the way up to windward and the mainsheet eased out to put the boom back on the centerline. I found out afterwards that they were using the traveler and sheet against each other to maintain the proper angle of attack on the lower 2/3 of the sail and keep it powered up. Meanwhile, the reduced tension from the eased mainsheet lessened the downward pull on the boom, which allowed it to rise and reduce leech tension. This opened the leech, twisting the sail so it could spill air off the top 1/3 and reduce heel. It works, because in conditions when others are reefing their mains, I can still carry full sail. This is really handy on the downwind legs. Even though this method works, tacking is a pain, and I suspect something is not right. That's when I recalled that the boat sailed better when the shrouds weren't as tight as they are now. I know from reading up on boat trim that allowing the masthead to bend off to leeward will open the leech. I also know that the H23 rig is very bendy. As described earlier it's a 7/8 fractional rig with approx. 5/8 of the mast above the swept-back spreaders. The mast section above the forestay is tapered. Compared to other boats of the same length, my mast is slimmer, the spreaders are at the same height or slightly lower, my forestay is about the same height as their masthead, and I have four or five feet more mast above the forestay. I will post a picture in the photo forum so you can see what I'm talking about. Those features (and experience with the adjustable backstay) tell me that the top of this mast was made to bend. The question is this...is lateral bend a part of the tuning characteristics of THIS rig? Assuming lateral mast bend is not part of the equation, then it seems that the vang is the answer to controlling leech tension. That way, the downward pull of the mainsheet does not affect the leech, i.e. the boom "floats". However, for that to happen, doesn't the vang have to be pulling down harder than the mainsheet was before? I need a beer. Peter H23 "Raven"
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Michael
Reply to Peter
Peter; I understand what you are talking about. Yes moving the traveler up and easing the sheet would depower by allowing some twist as the boom rises, but that is the technique used for lighter air. What I have read with that type of rig is to tighten the backstay to bend the mast and flatten the main. This is supposed to take the draft out of the main. It could be that it will fall off (bend) to leward due to the lack of support above where the uppers attach, but I don't believe it is for depowering the main. I am assuming that the upper shrouds do not attach at the mast head, and that the bending is above this point. Michael
Peter; I understand what you are talking about. Yes moving the traveler up and easing the sheet would depower by allowing some twist as the boom rises, but that is the technique used for lighter air. What I have read with that type of rig is to tighten the backstay to bend the mast and flatten the main. This is supposed to take the draft out of the main. It could be that it will fall off (bend) to leward due to the lack of support above where the uppers attach, but I don't believe it is for depowering the main. I am assuming that the upper shrouds do not attach at the mast head, and that the bending is above this point. Michael
Hi Mike
I just posted a picture of a couple of H23's in the Photo Forum, so you take a look at the rig. I listed the photo as relevant to the H90, but the title is "H23 rig for Guest Forum". The setup I described was for heavy air and yes, the backstay was on...to the max. There was no more adjustment and a clearly visible bend in the mast. I'm beginning to suspect that the main may just be too old and stretched out. Peter H23 "Raven"
I just posted a picture of a couple of H23's in the Photo Forum, so you take a look at the rig. I listed the photo as relevant to the H90, but the title is "H23 rig for Guest Forum". The setup I described was for heavy air and yes, the backstay was on...to the max. There was no more adjustment and a clearly visible bend in the mast. I'm beginning to suspect that the main may just be too old and stretched out. Peter H23 "Raven"
More on the Hunter 23 rig for Mike & Don
I was looking at the original of the photo I posted yesterday and I just realized that the upper shrouds do not go all the way to the masthead either. The only rigging at the masthead is the backstay. Peter H23 "Raven"
I was looking at the original of the photo I posted yesterday and I just realized that the upper shrouds do not go all the way to the masthead either. The only rigging at the masthead is the backstay. Peter H23 "Raven"
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