I own one of the Cherubini Hunters from the 70's. It's a 30 footer, tall rig I beleive. One of my biggest complaints about the boat is that it has always had too much weather helm. I have posted on the Cherubini forum a few times in the past and the consensus was that my sails were old and baggy and had too much draft that could not be taken out with the usual methods. I bought new sails and the situation did not improve. Last year for numerous reasons, the boat was hauled. I decided to be proactive about the helm issues. One related issue was that the rudder bushing was shot. Considering that they cut the bushing out of a peice of plywood, it's not suprising! I also addressed the horrible pintle-gudgeon design and improved upon that. I designed a removable boot so that you will not have to cut the skeg off of the boat to drop the rudder! The rudder is now rock solid and doesn't "groan" when under load. The cabintop between the mast base and compression post was built with a balsa core instead of something solid and totally rotten. I addressed that. I added a 6" stemhead extension. When I reset the mast base, I moved it forward 3.5 inches. I would have liked to move it further, but I obviously had to stay on the compression post below. These improvements have made a marked difference, but there are still helm loads, especially when beating to weather. Recently, we have entered a couple of club regattas. In prepration for that, we calculated the differential between tacks. Our best differential is about 100 degrees. I have heard that serious racers get down to 60 degrees between tacking angles. We were routinely outpointed, but did make up some of that difference with boat speed. However, with the helm issues, we are dragging the rudder and clearly hurting our top speed. I am sorry for the overly long preamble, I just wanted to give you the background. As far as sail trim goes, I have read "Sail Trim" by Wallace Ross numerous times among other books. I have raced on other boats and studied their technique. I feel like I understand what is appropriate trim for beating to weather, but need a fresh approach to the problem of weather helm. My opinion is that the boat is not properly balanced in sail plan and also has a wide beam which adds helm loads when heeled. With that beam, heel angle is probably more critical. One suggestion was to reef the main sooner than one would normally. But, I look at the other boats that we race against and they are all carrying full mains and big jibs and out pointing us like crazy.
Pointing Ability and Weather Helm
- Thread starter David Popken
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Two components
There are two separate issues. The amount of rudder angle and the force required to hold that angle. The rudder angle when fully powered up sailing to weather should be about 5deg (not more than 7deg). Depending on the design of the rudder and skeg, it may take quite a bit force to hold the rudder at that angle. As you noted, the helm increases with heel, sailing the boat flatter will reduce the weather helm. For most 30 foot boats that means 5-6 crew on the rail to carry full sail upwind. If the helm goes neutral when you dump the traveller down or ease the main right out, chances are that you should be reefed. Never mind what the other boats are doing. As a point of reference a Cat30 tacks through about 95deg in 6 knots of wind and just under 90deg in 14-16 knots of wind. You won't see 60deg tacking angles until you get into high end race boats. I'll guess that your best upwind boat speed will be about 4 knots in light air (6 knots) and about 5.5 knots when fully powered up in 14+. Play with trim and traveller, get the local rugby team on the rail and see how she goes.
There are two separate issues. The amount of rudder angle and the force required to hold that angle. The rudder angle when fully powered up sailing to weather should be about 5deg (not more than 7deg). Depending on the design of the rudder and skeg, it may take quite a bit force to hold the rudder at that angle. As you noted, the helm increases with heel, sailing the boat flatter will reduce the weather helm. For most 30 foot boats that means 5-6 crew on the rail to carry full sail upwind. If the helm goes neutral when you dump the traveller down or ease the main right out, chances are that you should be reefed. Never mind what the other boats are doing. As a point of reference a Cat30 tacks through about 95deg in 6 knots of wind and just under 90deg in 14-16 knots of wind. You won't see 60deg tacking angles until you get into high end race boats. I'll guess that your best upwind boat speed will be about 4 knots in light air (6 knots) and about 5.5 knots when fully powered up in 14+. Play with trim and traveller, get the local rugby team on the rail and see how she goes.
Boat speed and tacking angle
A lot of the reason the race boats get 60 degree tacking angles is they go fast to windward. The relative wind comes forward. An extreem example is a sailboard. They are seeing 40+ kts of apparent wind and can point just about any place they want. As for reefing when other are not, going to windward most of the force of the sail is causing heeling and not driving the boat so reefing will not necessarily slow you down. Infact it may (silly as it sounds) reduce your heel, which will reduce your weather helm which will reduce your rudder drag which will make you go faster!!! And think what the other boats will say when you beat them with less sail. IMHO if you reef your sail the other will probably think you know something they don't and reef theirs too. The differance between a professional and a novice is the professional has made more mistakes.
A lot of the reason the race boats get 60 degree tacking angles is they go fast to windward. The relative wind comes forward. An extreem example is a sailboard. They are seeing 40+ kts of apparent wind and can point just about any place they want. As for reefing when other are not, going to windward most of the force of the sail is causing heeling and not driving the boat so reefing will not necessarily slow you down. Infact it may (silly as it sounds) reduce your heel, which will reduce your weather helm which will reduce your rudder drag which will make you go faster!!! And think what the other boats will say when you beat them with less sail. IMHO if you reef your sail the other will probably think you know something they don't and reef theirs too. The differance between a professional and a novice is the professional has made more mistakes.
Cherubini Hunters .....
Most of the 30 ft. Cherubini Hunters were shoal draft @ 4ft. ... and this may present a problem in attempting to 'point'. I used to race on one and offer that unless the sailplan is well set/shaped that the boat will slip sideways excessively and possibly 'spin out' if the boat is heeled to excess when carrying heavy weather helm. Weather helm can be a problem but can remedied by adjusting the shape/set of the mainsail so that the position of maximum draft in the mainsail is well forward .... by applying LOTS of halyard tension and/or strong cunningham tension. An old woven dacron mainsail that has seen lots of service will contribute to excess weather helm .... a mainsail that has a shrunken 'boltrope'. Such symptoms will be: draft aft, very full draft, when the mainsheet is 'tight' the leech may be hooked towards windward .... and when the sail is 'just raised' and the halyard then tensioned an 'additional ~3 inches', the aft/end section of the boom will be lower than the gooseneck ( when viewed from the side when standing a moderate distance from the side of the boat). I dont have my sail specs. handy but such a sail should when properly raised and tensioned for shape/set should have the angle that the boom makes with the mast at about 88 degrees (boom aft end slightly higher than the gooseneck) . If the angle that the sail tack makes with boom is GREATER than 90 degrees (boom aft end lower than the gooseneck) ... then you have a shrunken boltrope in the mainsail. The remedy is to take such a sail to a sailmaker and have the boltrope 'eased' which will restore the proper maximum draft location to be more 'draft forward'. The amount of halyard tension is what positions the 'point of maximum draft' ... and that position affects weather helm more than anything else. Most sailmakers dont like to 'ease' a boltrope if the threestrand dacron rope in a sleeve at the luff has severely shrunken as it take a lot of work if the boltrop needs to be totally replaced ... and a new sail is not that more expensive. If the rope is only moderately shrunken it can be 'eased' to good effect - the forward sections near the luff will be 'flatter', the draft will be reduced and you will be able to apply more halyard tension to good effect. Every time you stretch and relax three strand rope, the rope gets a little fatter and a little shorter .... just ask your three strand docklines. Try this next time out (12-15kts). Get the boat to heel on a hard beat and note the amount of weather helm. If so, then apply bar-tight halyard tension on the mainsail and note if the helm hasnt become 'neutral' .... then slack off from bar tight halyard until you get 'just a wee bit of weather helm'. If so, take a magic marker and mark the halyard and its position on the mast .... so that you can return to this halyard tension anytime later - as a basic setting. If it takes 'extreme' halyard tension to get a 'neutral helm' then check the height of the boom end vs. the gooseneck with the sail 'just raised' and if lower at the boom end vs. the gooseneck .... take to a sailmaker and get the boltrope 'eased'. hope this helps.
Most of the 30 ft. Cherubini Hunters were shoal draft @ 4ft. ... and this may present a problem in attempting to 'point'. I used to race on one and offer that unless the sailplan is well set/shaped that the boat will slip sideways excessively and possibly 'spin out' if the boat is heeled to excess when carrying heavy weather helm. Weather helm can be a problem but can remedied by adjusting the shape/set of the mainsail so that the position of maximum draft in the mainsail is well forward .... by applying LOTS of halyard tension and/or strong cunningham tension. An old woven dacron mainsail that has seen lots of service will contribute to excess weather helm .... a mainsail that has a shrunken 'boltrope'. Such symptoms will be: draft aft, very full draft, when the mainsheet is 'tight' the leech may be hooked towards windward .... and when the sail is 'just raised' and the halyard then tensioned an 'additional ~3 inches', the aft/end section of the boom will be lower than the gooseneck ( when viewed from the side when standing a moderate distance from the side of the boat). I dont have my sail specs. handy but such a sail should when properly raised and tensioned for shape/set should have the angle that the boom makes with the mast at about 88 degrees (boom aft end slightly higher than the gooseneck) . If the angle that the sail tack makes with boom is GREATER than 90 degrees (boom aft end lower than the gooseneck) ... then you have a shrunken boltrope in the mainsail. The remedy is to take such a sail to a sailmaker and have the boltrope 'eased' which will restore the proper maximum draft location to be more 'draft forward'. The amount of halyard tension is what positions the 'point of maximum draft' ... and that position affects weather helm more than anything else. Most sailmakers dont like to 'ease' a boltrope if the threestrand dacron rope in a sleeve at the luff has severely shrunken as it take a lot of work if the boltrop needs to be totally replaced ... and a new sail is not that more expensive. If the rope is only moderately shrunken it can be 'eased' to good effect - the forward sections near the luff will be 'flatter', the draft will be reduced and you will be able to apply more halyard tension to good effect. Every time you stretch and relax three strand rope, the rope gets a little fatter and a little shorter .... just ask your three strand docklines. Try this next time out (12-15kts). Get the boat to heel on a hard beat and note the amount of weather helm. If so, then apply bar-tight halyard tension on the mainsail and note if the helm hasnt become 'neutral' .... then slack off from bar tight halyard until you get 'just a wee bit of weather helm'. If so, take a magic marker and mark the halyard and its position on the mast .... so that you can return to this halyard tension anytime later - as a basic setting. If it takes 'extreme' halyard tension to get a 'neutral helm' then check the height of the boom end vs. the gooseneck with the sail 'just raised' and if lower at the boom end vs. the gooseneck .... take to a sailmaker and get the boltrope 'eased'. hope this helps.
David - Talk about Frustration!
If you hadn't mentioned that you have new sails I would have suspected the sails too. However, that should have reduced or eliminated the problem but one thing that bothers me is you say "I bought new sails and the situation did not improve". Assuming the old sais were, in fact, old (read: "baggy"), then the new ones SHOULD have made a noticable difference. This is wierd but, oh well... What about rake, like how much rake is there? With the stemhead extention that would probably have maintained the original rake. If there is more rake than normal maybe the mast could be stood up a tad? As an aside, it's interesting that many of the Catalina 30s have short bowsprits too. With regard to tracking (not pointing) angle, how is bottom and prop? If you're in "racing trim" the bottom should be smooth and clean, and the prop should be a low-drag one. A fast bottom will help a lot with improving the tracking angle but a fixed-blade prop will absolutely kill you against the competition.
If you hadn't mentioned that you have new sails I would have suspected the sails too. However, that should have reduced or eliminated the problem but one thing that bothers me is you say "I bought new sails and the situation did not improve". Assuming the old sais were, in fact, old (read: "baggy"), then the new ones SHOULD have made a noticable difference. This is wierd but, oh well... What about rake, like how much rake is there? With the stemhead extention that would probably have maintained the original rake. If there is more rake than normal maybe the mast could be stood up a tad? As an aside, it's interesting that many of the Catalina 30s have short bowsprits too. With regard to tracking (not pointing) angle, how is bottom and prop? If you're in "racing trim" the bottom should be smooth and clean, and the prop should be a low-drag one. A fast bottom will help a lot with improving the tracking angle but a fixed-blade prop will absolutely kill you against the competition.
Well.....
Mainsail is only about three years old, w/full battens and still pretty flat. Halyard tension is key, or Cunningham tension in leiu of haylard tension. As far as suggestion to use a bigger headsail, when you overlap the main, that part of the headsail that overlaps contributes to shifting the CE aft and therefore increases the weather helm tendency. The mast rake is neutral. Before the haulout, I had the mast raked forward, but only slightly and it did not seem to help that much. I am tempted to rake the mast forward again. With the other things that I have done to move the CE forward, tht might make enough difference.
Mainsail is only about three years old, w/full battens and still pretty flat. Halyard tension is key, or Cunningham tension in leiu of haylard tension. As far as suggestion to use a bigger headsail, when you overlap the main, that part of the headsail that overlaps contributes to shifting the CE aft and therefore increases the weather helm tendency. The mast rake is neutral. Before the haulout, I had the mast raked forward, but only slightly and it did not seem to help that much. I am tempted to rake the mast forward again. With the other things that I have done to move the CE forward, tht might make enough difference.
Some boat are just cranky ...
My C30 was perfect with a blade and single reef sailing on SF Bay in 18-22. In light air it has lee helm that kills upwind performance. I added the bowsprit and a bigger headsail, then a bigger large roach main and raked the mast aft until I got decent light air performance (now sailing in Vancouver). Now when it blows the boat has WAY too much weather helm, unless I have 1200# of crew on the rail. The solution I've come to is to set the boat up so it sails right with a full crew (I can heel the boat to leeward with crew weight to get some weather helm in light air)and I add a toggle or two to the forestay when I'm sailing in light sail and short handed. Beamy boats all tend to have this problem to some extent. The best that you can hope for is pretty good with your normal crew under the conditions that you sail most often. when you go outside that envelope expect to find some handling "personality" that may not please you.
My C30 was perfect with a blade and single reef sailing on SF Bay in 18-22. In light air it has lee helm that kills upwind performance. I added the bowsprit and a bigger headsail, then a bigger large roach main and raked the mast aft until I got decent light air performance (now sailing in Vancouver). Now when it blows the boat has WAY too much weather helm, unless I have 1200# of crew on the rail. The solution I've come to is to set the boat up so it sails right with a full crew (I can heel the boat to leeward with crew weight to get some weather helm in light air)and I add a toggle or two to the forestay when I'm sailing in light sail and short handed. Beamy boats all tend to have this problem to some extent. The best that you can hope for is pretty good with your normal crew under the conditions that you sail most often. when you go outside that envelope expect to find some handling "personality" that may not please you.
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