re: advice from Mike, Scott,
Doghouse.... let me try to explain my previous comment regarding all this "advice" and why it pays to get a consistant instructional to make things less confusing.Mike's comment was that the vang reduces the "belly" put in the mainsail by big winds. I would challenge this statement and suggest that the belly or increased draft depth is controlled by other devices, such as the outhaul or backstay or what ever control you use to induce mast bend. The fact is when sailing downwind or on a broad reach you WANT a fuller, rather than a flatter, sail. So the vang allows you to control the twist on these points of sail since the mainsheet is too far extended to pull down on the boom. Easing the backstay, the outhaul, the halyard and the cunningham will allow a fuller sail with the vang controlling the curve of the leech (twist). Applying the vang does not remove the belly, it closes (straightens) the leech of the mainsail. If you are trying to depower the main on a close or beam reach you want the leech opened (twist). Sailing upwind, you remove the "belly" by applying the aforementioned controls to achieve a flatter sail as conditions dictate. That said, some boats may be able to induce a bit of mast bend by using the vang to push the boom forward... on a dinghy for instance. On my masthead rigged Cat 27 it doesn't have any effect. Now, Scott's comment was truthful in that he admits he is a new sailor. Throughout his post he says things like "it seems to me" "I rarely tweak the device" or "I am relatively new and inexperienced" I won't criticize him for making the effort but you must realize that the quality of the advice is limited by the experience of the advisor. If you can get past Don's sales pitch you'll find some solid info from an experienced teacher. (love 'ya don, I have your book and chart)I'm not an old salt (well, old, maybe) but I've enough experience to advise you to start a library so you can get some of your questions consistantly answered by qualified experts. Here's a link to some online instruction you might find beneficial.