[Brian Duff]

Ian is correct. The hull trim of a boat is a significant factor in balance under sail. So is the heel angle. All of these need to be correct before adjusting rake. As IAN SAYS the bend of the rig and rake of the rig come in as very fine tune adjustments meant to effect the ability to keep a balanced helm through a range of conditions, assisting the sailor in keeping the balance and heel of the boat with a constant trim and heel.

A tough task on a larger keel boat sailed short handed. This is probably why many find keeping a small amount of weather helm allows the boat to sail itself well. There is also a theroy that slight weather helm on a keel boat can help create lift to weather, but this is dated and only applies to certain hull types...

On my cruiser (westsail 32) i have to battle constantly with Lee Helm. This is (i think) BECAUSE the boat is really STERN UP due to having no engine and not nearly enough extra ballast to bring the boat to her lines. THis causes the whole rig to be well forward of where its intended, and the hull to be shaped all wrong. In my case I have an extra bronze windlass, a few hundred feet of chain and acouple extra anchors as well as a few batteries back in the engine room, and the boat is still up in the stern by 4" or more. The bow is basically on its lines, about 1" under due to the stern being so high. One would think this would make the boat have a wicked weather helm from hull trim, especially since the W32 is known for slight weather helm (which I have always been able to tune out of the boat to achive complete self sailing upwind) but my boat battles lee helm (maybe from rig trim). I have however added toggles unde the forestay and shortened the backstay chainplates by lowering the boomkin angle. My goal for this winter is to put an engine back in to bring her onto her lines, and help with re-sale value. That said, in the BVI where we keep her an engine is JUST NOT NEEDED. I hope she sails better then...

So, that is a sign that balance of hull is way more important than rig in getting the boat to sail well, (as Ian said) and that the convention of weight foward heads her up and weight aft lets her fall off doesn't allways apply.

Now a second case -Gaff rig cutter from west coast of england, (shirmper really) this boat came with wicked weather helm, i believe intended as she was meant to tow shrimp nets off her leward quarter post and mast, such that the helm would become netural with alot of power still available. To use this boat as a yacht a few things were tried. The hull trim was adjusted as much as possible using human ballast (group of 6 folks adjustnig from one end to the other but that seemed to have no effect) First was a 4' longer bowsprit. That helped alot. next we tried cranking the rig forward, it got worse! Letting the mast fall as far aft as we could helped things better again on the helm, but the boat i think is just meant to have helm unless towing...


So all that leads us to just have to get each boat on the water , balance and trim correct, then judge sail and rig shape to start the guessing game toward correct sailing balance. its fun. it doens't always make sense.

Sailing unballasted dingies can help A LOT to understand balance under sail, sail shape and rig tuning too....

To explain about rake and bend - Theroetically rake aft will increase tendancy to round up, and visa versa. Mast bend increased will typically encourage the boat to be able to point closer to the wind and heel less. Forestay increase in tension typically makes the boat heel less, and point highter. Decrease in forestay tension decreases pointing and adds power (or heel). The reason max depth of sail (minimum mast bend, max forestay bend) is not fastest is that as the boat heels too much or you have to flogg sails to keep on trim, you create drag. Rather than luff sails partially - flatten them.

Any more clairity through all that rambleing? i hope so