Tuning- initial setting, weather helm and rake

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: In response to a question about how to get rid of "wicked" weather helm: : The first thing regarding weather helm is to be sure the boat is flat and sailing on her lines. A small heel (5-15 degrees) can create tremendous weather helm that no amount of tuning can remove. If you are out in a breeze you have to de-power the main...this means flattening it (lots of outhaul...to the max, lots of boom vang, to bend the mast forward thus pulling cloth forward and reducing the draft of the sail, and maybe some cunningham downhaul...to further flatten the front of the main- how much of each of these depends on the conditions, but a rule of thumb is more of each with more wind). : Initially, I'll assume your centerboard is in a suitable position. I have the leading edge of my board when in a vertical position set back as far as allowed (2600 mm ‰ 102 3/8 inches from the aft face of the transom). If yours is within an inch or two of this position, you should be able to get the helm out as described below. : Assuming you are sailing the boat flat, here are some suggestions as a starting point for tuning. Note this is just a starting point, from here you will have to fine tune for your boat, sails, crew weight...etc. : 1) Place the foot of the mast as far forward as allowed (3350 mm ‰ 131 7/8" inches from aft face of transom to forward face of mast) : 2) Set spreaders (optional) : This will control mast bend. As a starting point have length of spreaders about 17 inches from the point of contact with mast to the side stay wire. Rake the spreaders aft such that a line drawn from tip to tip on the spreaders is about 6 inches behind the aft edge of the mast. : 3) Assure mast is centered in boat (i.e. side to side). : Do this by putting side stays in the same hole setting on each side of boat. Raise jib only (no main) and tighten halyard to tension rig as if sailing. Hold main halyard to use it as a straight edge to site up back edge of mast. If mast is bent side to side, relieve tension, adjust side stay settings (up or down a hole or two) and re-tension. Repeat until there is no lateral bend to the mast. : 4) Set Rake : Set the rake by the position of the side stays (not the forestay). You will set the side stays as "stops" so that when rig tension is applied to the jib halyard, the mast will move forward until constrained by the side stays. : The following measurement scheme is a bit unusual, but it is the easiest to do. With jib up, detach forestay and allow it to rest next to the mast. With tape, mark the forestay at the top edge of the black band on the mast (if you don't have a black band, mark where the top edge of the boom attached to the mast). : Lead the forestay back to the bow and attach. You want to set the rake such that when the rig is under tension for sailing, the point you just marked on the forestay is about 28 inches from the tip of the bow. You do this by adjusting the side stays in the chain plates (not the jib halyard tension). : Keeping the side stays even (i.e. in the same relative positions on port and starboard chain plates), drop or raise each side stay the same amount (number of notches or adjustment on the turnbuckels) until the 28" measurement is reached when the jib halyard is full tensioned for sailing. : This probably translates into the tip of the mast being about 12-16 inches behind the foot of the mast- but this is a guess, not an accurate measurement. The boom should be about level or slightly down at the aft end when hanging at rest. : 5) Go sailing and try it out : With the centerboard vertical (i.e. perpendicular to the waterline of the boat) you should have nearly neutral helm with this set up. Try it and see. Remember the boat must be ABSOLUTELY flat (NO HEEL) to test this, so pick a day that is not too breezy. If the boat has weather helm remove rake by moving the shrouds up in the chain plates. If it has lee helm, add rake, buy lowering the shrouds in the chain plates. : This should get you started. If it does not work, get back in touch with me or Barney Harris (barnstorm@compuserve.com). Barney is the real tuning guru in the class. He is particularly good with North sails. I sail with Sobstads. : I will post this on the Albacore forum (http://www.my-town.com/sailing) so other with ideas can offer their advice. : Let us know how it turns out... : By the way, what boat number do you have? Do you know the mfg. of the boat and sailmaker? : Peter Duncan : Sailfaster @ aol.com : Albacore #342

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