Weather helm

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Jul 25, 2005
43
NULL NULL Boston
Need some help with excessive weather helm (EWH). EWH = wheel rotated 90-110 degrees to lee. My rudder is 3.5 turns stop to stop. Conditions: 12-20 kn, close haul, close reach, 30' sloop, masthead rig, full main trimmed flat, 140% genoa, mast raked 3-4" head to deck (fixed no adjustor), maintaining same heading. I am trimmed and getting what I think is EWH for the conditions. I know I can reef the main and reduce the effect but I think there may be trim to adjust before reefing. When pointing and the wind increases or shifts slightly, I drop traveler to reduce EWH, maintaining a flat main and trimming genoa to maintain differential air flow/slot. Heel is not more than 25-27 degrees. Still trying to Wind kicks up more, traveler is dropped to max, still have EWH, heel at 25-27. I then add twist to main to spill air at top and trim genoa to match. Any further mainsheet/genoa reduction results in lufting sails, loss power. If I trim main/genoa slowly I end up with EWH. So here is my order of trim: Drop traveler Add twist (less vang, less mainsheet) Reef main Is reefing main the only solution here? BobD Boston
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
You have almost everything right. The solution will not be easy for you. At first I thought you were cranking on the mast but it appears you or someone set the rake. The first thing to do is eiminate the mast rake. Keep the mast straight up and down. You might think that 3 or 4" is not a lot but it does not take a lot of rake to cause your problem. When the mast was raked it effectively move the mast aft on the deck. A local rigger can help you fix the problem. Next, your heel should not exceed 15 degrees. You want to keep as much of the rudder in the water as you can. At 25 degrees of heel the mainsail is acting as a giant rudder and over powering the rudder. Try those 2 things and I'll bet your weather helm goes away.Correcting the heel is easy. The mast is another matter.
 
T

Ted

EWH

What condition are your sails in? Old dacron main sails will tend to have a more draft aft shape as the wind increases which in turn will give you more weather helm. Try some more halyard or cunningham tension to get the draft forward. If you have a adjustable baby stay or adjustable backstay, try bending the mast to flatten the main some more. If your boat has a narrow waterline beam you can carry 25 degrees or more of heel without loosing boat speed. Every boat is different. If all else fails, Reef.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
What type of keel does she have?

Sounds like you are trying to point to high to windward and are over canvased. With a shoal draft keel this can result in a lot of heel and lots of weather helm. On my Legend 37 w/shoal draft fin keel and spade rudder I have come to the conclusion that reefing the main and/or letting out the boom to leeward actually makes the boat stand back up and allows me to point just as high and without loosing speed. At 25 degrees of heel you are really going to have to do something besides trim the sails. Remember the healing force does not make the boat go forward. The more perpendicular the sails are to the line of travel the more effective they are at providing driving and not healing force. When the boat is healed way over most of the force is going to making leeway and not to propelling the boat forward. You also get a change in the plan view of the boat undersides which can DRASTICLY effect the helm. Reef and get her standing back up straight.
 
Jul 25, 2005
43
NULL NULL Boston
EWH problem

Don, Rigger set the rake. I thought I'd keep the rake as is to flatten sail when needed because I have not fitted a cunningham. I'll consider adjusting rake to plumb mast and try again, but... Bill hit on a datum I did not inlcude. I do have a shoal draft (4') fixed fin keel. I don't think I am pointing too high (pinching?) and the heel was a MAX of 25-27, more typically it is in the 18-22 range except in gusts when I heel and round-up. I understand the aerodynamics of sail/keel/rudder, but I thought I had enough keel depth and ballast for the rig. I single hand often and wanted to eliminate trim problems before putting in a reef. Sailing with the single reef does indeed tame the ride. Guess I'm stubborn. Ted, I may fit a cunningham to flatten the sail to the max. The mainsail has about 9 yrs wear, but not by any means blown out moving the draft aft. Good advice all! Thanks BobD
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Rake vs Mast Bend

Bob: The problem is mast rake does not flatten the sail. The sail is flattened by mast bend. Mast bend and rake are 2 different things. Unless you have a "bendy mast" like a J boat you can not bend the mast. To illustrate mast bend, look at your index finger straight up and down. Now bend it. That bending in the middle is what pulls the ecess of the sail, which the sail maker built in, out of the middle thus flattening the sail. Rake your finger back and you'll see nothing happens to the middle of the sail. Windsurfers use rake all the time. When they rake the mast back the board turns into the wind. When they rake the mast forward the board turns away from the wind. Weather helm is not a bad thing. When sailing upwind you want about 3 to 5 degrees of weather helm and the reason is simple. You get lift from 3 sources - the sails, the keel and the rudder. Most sailors like a neutral helm but that is a mistake as they lose the lift from the rudder. I'm not a rigger and have never sailed on your boat so what do I know but in my opinion your excessive weather helm is caused by nothing else than your mast rake.
 
R

Robert Moretti

try a cunningham -- you'll like it

I sailed for years without a cunningham for the main. Then I read somewhere that the use of one can help delay the point at which you have to put the first reef in. Since I'm primarily a singlehander, like you, I want to everything I can before having to reef. When I finally made up a cunningham, I was surprised at the difference it made. Much, much easier to adjust than the main halyard, so I can tension the luff better than I can with only the halyard.
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Cunnigham

Robert M: Exactly my sentiments - totally easier and more efficient than the main halyard due to the mechanical advantage. Some may not agree with us but that is what makes the world go round.
 
Jul 25, 2005
43
NULL NULL Boston
Rake vs Bend

Don, Thanks for the distinction between the terms. Using your definitions I used 'rake' when I should have used 'mast bend', the aft curl mid mast to head - thus the ref. to flattening sail. Now - I'll need to examine whether I actually have a raked mast. I guess I would use the halyard as a plumb line reference. Re: 3-5 degree WH, the Sail Trim guide refers to this, Is this 3-5 D of rudder angle from center? This winter I'll do the math to figure the rudder angle to wheel turn angle ratio. ...Hmmm. Let's see, a 36" wheel to a 4" pinion to a 15" quadrant....or Hey honey, tell me how much the rudder moves when I turn the wheel.. BobD
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
3 to 5 degrees rudder

Bob D: 3 to 5 degrees of rudder is not very much. On my boat (C30) it is easy because the emergnacy rudder post sticks up through the cockpit floor so I use that point of reference as my guide. Once you fool around with this you will get to a point where you can actually feel it in the wheel. It is a lot easier with a tiller. On plumbing the mast - hopefully others will chime in here. I don't know if the halyard will work. It may be OK for a rough estimate but I think a lot of guys use a plumb bob bur I don't know exactly what they do. I'd have a rigger do it myself. If the rigger insists that the rake he tuned in is OK ask him to explain why.
 
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