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Discussion Starter · #1 ·
I have had my 32' ketch for 4 years now and am still trying to get it tuned right. It has a non adjustable Furler with a 150% Genoa on it for the front stay (can't be tightened.) When I got it the Stays were all very loose. It had good weather helm like that but was very sloppy because of the Stays. I tightened the stays all up which helped a lot but now it has way to much weather helm, almost unmanageable. My assumption is I need to tighten the front stay and loosen of the Back stays but how to best do this. Since there is no adjustment on the front stay I assume I have to either shorten it, which would be tough to do as it means messing with the Furler, or moving the mounting plate (whatever it's proper name is) at the Bottom of the front stay forward and putting a turnbuckle in for adjusting. Would doing that cause me other problems? Hope I explained this well enough.
 

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You should probably do the other way around! ie tighten the back stay, which would also tighten the forstay, putting the mast slightly raked aft, which would put the CE of the sails back a bit, which should lesson the weather helm some.

You may also have to work with the actual tuning of the sails to figure out how to lower the weather helm too.

Have you looked at the rig tuning at the top of this area? While aimed at single mast boat, some of the how to may make making sure your tune is correct.

Marty
 

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Discussion Starter · #3 ·
I think I am confused on this in the Rig tuning thread (and everything else I've read on this) he says "Aft Rake increases weather helm, improving pointing, forward rake does the opposite.My problem is that I have to decrease weather helm which would suggest to me that I need more forward rake. Before I tightened the Back stays The weather helm was good. I tightened them and got way to much. The more I tighten them the worse it gets.
 

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You should probably do the other way around! ie tighten the back stay, which would also tighten the forstay, putting the mast slightly raked aft, ...
You'd think so, but it doesn't work that way, oddly enough. I had read that rake is solely a function of forestay adjustment/length, and that tightening/loosening the backstay doesn't affect it. "That doesn't make any sense," I thought. But then I tested it while adjusting our rig last spring. Sure enough: Tightening/loosening the backstay did not affect mast rake! Weird, but true.

superiorvoyager: Check Alex' (Giulietta's) rig tuning guide, Adjusting Your Rig, listed as a sticky at the top of the Gear and Maintenance sub-forum. (I'd just stick the URL in here, but Sailnet's stupid automatic link-a-word-to-crap-they-sell software destroys URLs that link to their own forum posts) and/or Ivar Dedekam's Sail and Rig Tuning. If you've too much weather helm, you do indeed want to reduce mast rake. Then again: You have a ketch, and everything I've studied is for sloop-rigged boats. I don't know how much of the above applies to a ketch-rigged boat.

How you can adjust mast rake with a non-adjustable furler is something I've no clue about. It sounds like "surgery" is in order, perhaps?

Jim
 

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How about an adjustable "Chainplate" on the front stay? My front chainplate has multiple holes (fore and aft) to loosen or tighten the forestay. I'm not sure this would work, My experience is just on my little sloop.
 

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It has a non adjustable Furler with a 150% Genoa on it for the front stay (can't be tightened.)
This may not be the case actually. Most furlers allow for forestay adjustment. It is usually a convoluted process requiring a certain amount of disassembly of the unit, but it should be possible. Google the manufacturer's website. If there are no manuals online there for your particular unit, email the manufacturer and ask for directions.

Weather helm increases with rake. As the center of effort moves back the boat will have a greater tendency to head into the wind.

When the forestay is loose, tightening the backstay will move the head of the mast back, thereby inducing rake. BUT as soon as the forestay is tight, shortening the backstay has the effect of bending the mast forward which flattens the belly of your mainsail.

If, after tightening the forestay, there is still excessive weather helm, try getting new sails, or having your current ones recut. A blown sail makes a big difference. If there is still a problem, then you could think about adding a short bowsprit to the boat.

Good Luck !
 

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Discussion Starter · #7 ·
An adjustable chain plate is kind of what I was thinking. That would move the point where the stay ataches forward a bit but I supose that wouldn't hurt.
 

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I think I am confused on this in the Rig tuning thread (and everything else I've read on this) he says "Aft Rake increases weather helm, improving pointing, forward rake does the opposite.My problem is that I have to decrease weather helm which would suggest to me that I need more forward rake. Before I tightened the Back stays The weather helm was good. I tightened them and got way to much. The more I tighten them the worse it gets.
Superiorvoyager, you were correct to start--increasing rake, moving sail draft aft on the boat, would increase weather helm, as I think SEMIJim clarifies above.

I'm no rig tuner, by any stretch, but I would think you'd need to tighten the forestay to decrease rake noticably.

All that said, rake might not actually be the source of your weather helm problem. Weather helm means the draft of the sails is too far aft. Mast rake could cause this, but it could also be that the sails are too stretched out or not properly adjusted, resulting in mainsail draft that's moved after of where it should be. The solution if that's the case would be to have the main recut, if possible--replacement would be great too, but obviously much more $.

I would at least try sail adjustments (outhaul, leech, etc.) before pulling off the rolling furling unit to tighten the forestay. Just my two cents...

Good luck!
-J

P.S...added later -- Looks like others before me have posted pretty much what I did--I took to long to submit my post! :)
 

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Weather helm can be caused by many factors or a combination of many. Too much forward rake and your boat won't perform well, too much aft and you'll increase weather helm. Sails, sail trim & sail condition are generally the biggest contributors to weather helm.

Perhaps if you can describe your rig, sail plan, stay configuration, brand of furler etc. etc. perhaps we can help you better...

I've sailed on a few boats that were just poorly designed and there was not much you could do to eliminate it other than expensive mods like a new rudder..
 

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Discussion Starter · #10 ·
I was assuming that the problem is in the rake since it started when I tightened the Back Stays. Problem is not in the sail adjustment (if it was adjusting would have helped. If I loosen the Back stays and let front and back stays just flop the weather helm improves but of course, the noise caused by stays tightning and loosing in the wind and waves, not to mention the stress put on the rig from all the jarring makes me think I shouldn't leave the stays slack. So I know I can get rid of the weather helm by having loose stays but obviously that isn't desirable. The front stay isn't adjustable so I need another solution. I don't have the manual here with me (It's on the boat under 4' of snow) but It says it was designed for use on a chainplate with a number of holes for fine adjustment. Otherwise it sugested sending back to the supplier and having it shortened. Right now it is on the farthest forward hole so I can't adjust it more. I can move the chain plate forward or make a new chain plate. I was planning on making an anchor roller for the bow of the boat so could possibly make a new chainplate/roller combination. My thought if doing this was to move the point of attachment forward and put a tunbuckle of some sort in so I can adjust it. This would move the point at which the bottom of the stay attaches 4-6" forward though and I have no idea if that would just cause more problems.
 

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Discussion Starter · #11 ·
As far as my set up goes If I can figure out how to post a picture I'll do so. The Boat is ketch rigged, Mizzen is 71 sq. ft. Main is 136 sq. ft. and jib is 199 sq. ft. but I always use my 150% genoa. Can't remember the make of Furler and the boat is currently buried under snow at the yard.
 

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Joys of weather helm...

Rake of the mast is a tool.. however not the sole contributor of weather helm.

Basically put - the less wind the more rake - the more wind the less rake you want to have. The idea behind that is is shaping the genoa and the main for the conditions - but honestly, is not a main contributor to weather helm.

So what about the weather helm. On most boats - it will be trimming the main properly.

Spilling the main comes in different flavors.

Some just slack the main and ease the traveler so it is 60 degrees or more off.

Me, I tend to bend the main more in heavier winds and spill it where it should matter - at the top. This means you bring the traveler to 2 inches from center - offset on the leeward side. Give slack to the mainsheet enough to curve the main - and you spill in just the right area. If still weather helm then you ease the Genoa a hair.

It'll be a play as you go - but that will most likely be the area you want to concentrate on to correct the weather helm. The mizzen is not really a contributor in this scenario and many never sail with it up in conditions where you experiences indicate that you are.
 

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Discussion Starter · #14 ·
With very light wind there still too much Weather Helm. In a stiff breez which I often sail in I can totally depower the Main and Mizzen, spill all the air and still be turning into the wind I have to drop the main and Mizzen to get rid of it. Since the problem started when I tightened the Back Stays it makes sence to me that I need to reduce the rake that I induced when I tightened them but to tighten the Front stay I need to eiher Shorten the front stay or move the chain plate forward. Shortening the stay with this Furler is a major job so Moving the chain plate forward seems the better option but I am wondering if that will have an adverse affect in some other way? Maybe the only way to find out is to go to make a new chain plate move it and see what happens.
 

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Physics is physics and there ain't much you can do about it. It's a simple (in theory) lever problem. The main pushes the bow upwind (weather helm) and the jib pushes the bow downwind (lee helm). In a fixed keel boat, when you have excessive helm, lee or weather, you can do two things. You can change the length of the lever by adjusting the rig (thereby moving the centers of effort of the sails) or you can change the force by powering or depowering the appropriate sail. I suspect that your rig was slack for a reason. The PO probably found out that he had too much weather helm, couldn't trim it out and didn't want to bite the bullet by changing the rig. Moving the anchor point is a crap shoot. How much is enough? Have you talked to a rigger?

Dick Pluta
AEGEA
Nassau, Bahamas
 

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With very light wind there still too much Weather Helm. In a stiff breez which I often sail in I can totally depower the Main and Mizzen, spill all the air and still be turning into the wind I have to drop the main and Mizzen to get rid of it. Since the problem started when I tightened the Back Stays it makes sence to me that I need to reduce the rake that I induced when I tightened them but to tighten the Front stay I need to eiher Shorten the front stay or move the chain plate forward. Shortening the stay with this Furler is a major job so Moving the chain plate forward seems the better option but I am wondering if that will have an adverse affect in some other way? Maybe the only way to find out is to go to make a new chain plate move it and see what happens.
You are saying that with out the main or mizzen up you still have weather helm? Do you have a rudder problem? What ever is going on it's not right. Under the head sail alone and a centered rudder you should be falling off the wind.
 

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I think you answered your own question in the first half of the op.

Rule #1 The last thing mucked with is the first thing to go wrong.

The boat sailed ok untill you adjusted a loose rig by adjusting the wrong stay. Agreed it was the only way to tighten the rig but it was wrong.

If you want to try increasing the range of the adjustable fwd chain plate idea and it works ok then there you go. You might however move something else out of design specs.

I'm thinking a shortend forestay is the answer and you may just have to bite the bullet. You might want to consult with a professional rigger if you haven't.

With very light wind there still too much Weather Helm. In a stiff breez which I often sail in I can totally depower the Main and Mizzen, spill all the air and still be turning into the wind I have to drop the main and Mizzen to get rid of it. Since the problem started when I tightened the Back Stays it makes sence to me that I need to reduce the rake that I induced when I tightened them but to tighten the Front stay I need to eiher Shorten the front stay or move the chain plate forward. Shortening the stay with this Furler is a major job so Moving the chain plate forward seems the better option but I am wondering if that will have an adverse affect in some other way? Maybe the only way to find out is to go to make a new chain plate move it and see what happens.
 

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How much heeling are yoiu experiencing when have trouble with weather helm? Weather helm due to heeling would have no relations to your rigging dynamics. If you are sailing " In a stiff breez which I often sail.." with a 150% I would suspect you will heel a lot, and suffer weather helm, even if you are luffing the main and mizzzen...which touches on another issue...the mizzen would be a major source of weather helm... in a "stiff breeze" either the missen or the main should be fully furled and out of the picture. Note also that a lot of older hull designs...no matter how pretty they look...were not particularly well balanced... the weather helm was simply designed into the hull.

I would make sure you have your trim practices down perfectly before you start re-designing your rig layout.
 

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Discussion Starter · #20 · (Edited)
By dropping the main and Mizzen I get rid of the weather helm although it doesn't fall off as much as one would expect. When I first tightened the Back stays it was for the purpose of tightning the rig up as everything was moving around when sailing. The weather helm problem was an unfortunate consequence. When sailing into the wind I ussually drop the Mizzen but since messing with the rig that doesn't work anymore. Certainly Dropping the Mizzen and Reefing the main (or dropping the mainand reefing the Mizzen) helps but even in a light (under 10 knot) wind there is still too much helm unless I do so. The Voyager is a real pig in light wind so I need the sail area in light winds. I've played with the trim a lot and can't compensate for the problem. I have a fairly good understanding of trim with close to 40 years sailing . Unfortunately most of that was racing Lightnings and Lasers which is different than cruising but principals should still be the same. In anything over 15 knots the tiller is way to much work. What I think I'll do is try loosening the Back stays again and tighten the front stay first by moving the chain plate a little forward (I am having a new Chainplate/anchor roller made anyway) and see if that works. Since no one can predict if it will cause any other negative consequences I'll just give it a shot and see. Again, I don't know any riggers and there arn't any here to help me out. I sail out Of Nipigon Ontario on the very Northern Tip of Lake superior, actually we are the most Northern Fresh water Port in North America and give out certificates to prove it. Lots of Motor boats up here but very few sailboats.
 
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