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Rig TuningMike Calvert talks about friggin' with your riggin' - Summer 2002 |
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This article follows on from Graham Williamson's epic report on
mast set-up. So read and digest, then we're ready to begin... Now I realize some boats are rigged differently, but you should be able to recognise and locate the bits I'm talking about on your boat. If not, we expect to see you at the training weekend next year! Graham has now given you all you need to set up your mast correctly in your boat. So how do you to arrive at, and duplicate fast settings? The answer is to calibrate the main rig controls so that you can tell at a glance where everything is set. The controls that you should mark are the jib halyard, shrouds and lowers. (If your boat has a strut instead of lowers, same principles apply.) It is very important to do all your set-up markings on the shore, as it is almost impossible to tell what the rig is doing whilst you are sailing. Start with the mast at its fully upright position, and mark on your first jib halyard mark. Have just enough shroud tension to take up any slack in the rig, but not enough to bend the mast. Then pull the lowers on until the mast just starts to move backwards, and cleat off your control line. Mark the lowers with a tape strip somewhere easily visible, and where the lowers purchases have the most movement. I mark mine on the forward deck support post, lining up the tape strips with the top of the lowers pulley block. Most current deck-stepped rigs should be able to use this system. Other types will require improvisation! Then move the jib halyard hook up to the next mark, check your shroud tension and lowers as before, and put a new tape strip mark at the new lowers block position. Repeat this for all your jib halyard marks, so you now have a set of lowers marks to correspond with your jib halyard settings for the full range of rake. Next you need to have some reference marks for your shroud tension. All you need is three equally spaced marks, placed well apart, by the shroud purchases. I mark mine on the on the aft deck support post, under the mast step. These marks don't actually correspond to anything; they are just used as an instant visual guide to enable you to quickly duplicate tension settings, according to sailing conditions. So how do you use these marks on the water? Best to start with medium wind conditions, and somewhere where there is plenty of room and steady breeze. If at all possible two-boat-tune with somebody of equal speed and ability, and that you can trust to give you honest feedback! Start with your jib halyard and lowers at corresponding settings appropriate to the wind conditions - e.g. in a force 1-2 use your first marks. Sail to windward and adjust your lowers a little either side of your mark, to see if you can gain any extra performance. Always try the settings on both tacks! Then try a little more or less rig tension, and see what happens. The general rule with rig tension is to keep the leeward shroud just tight. Be careful, as in a blow this can be a huge amount of rig tension! There is a lot to be gained by experimenting with rig tension, as it has a dramatic effect on mast bend, both fore and aft, and sideways. Experiment further in different wind conditions. Remember, your marks give you a datum to work from - so you always have a standard setting to go back to. And finally... Don't become over preoccupied with tuning - boat speed is great, but you can gain much more by starting well, and getting the shifts right. Remember if you are twice as fast, you can go twice as far in the wrong direction!!! Mister Mikey's Top Tuning Tips Only adjust one thing at a time and assess property what is happening. Remember that for a given wind speed, your settings will need to be different for flat water, or wavy stuff. Take your time - getting the best from your rig doesn't happen overnight! Got some new sails? Make sure the jib luff wire is the same length as the old one; otherwise all those lovely marks won't mean a thing! See also: Setting up the mast - Graham Williamson Calibrating the Rig - Graham Williamson How To Tune |