
11-08-2005
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Junior Member
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Join Date: Mar 2005
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telltales
I wrote thie following article for a sail trim forum on another network but I thought some beginners here might get something out of it.
Mates: Anyone who knows me or has read my book knows how much importance I place on telltales. In fact, I don''t know how anyone trims their sails without them. For the price of a package of gum (I remember when it was only 5 cents!!) you can attach telltales to your main and jib and the results will be that you''ll be able to sail your boat more efficiently and definately faster - that is provided you know how to read them.
In addition to the normal telltales attached to the main and jib I also attach them to the shrouds and backstay. These telltales indicate the direction of the apparent wind. Knowing the apparent wind angle helps you trim your sails on all points of sail. They also save your neck the discomfort of craning your neck to look at the masthead fly.
Telltales provide an enormous amount of information about the airflow over your sails. This information allows you to trim your sails with greater accuracy.
The most important mainsail telltale is the top one. It is the primary guide for judging mainsheet tension and trim. When sailing closehauled you want the top telltale streaming. What that is telling you is that you have "attached airflow" along the entire curve of the sail. You''ll sacrifice a little pointing ability but you''ll definately be getting 100% efficiency from your mainsail. If you want to point a little higher, trim in the main until the top telltale JUST stalls. What that is telling you is the airflow is not completely attached along the entire curve of the sail. You''ll point higher but you''ll be slower than if the telltale was streaming. Actually, your most efficent when the top telltale streams half the time and stalls the other half of the time.
When reaching you want to trim the mainsheet and boom vang so all the telltales stream aft. This results in maximum speed. How you achieve that mode is simple. First ease the sheet until the main JUST starts to luff and then trim in a little. This is called "triming to the point of draw". Next start to tension the boom vang until the until the telltales JUST start to stall and then ease off on the boom vang slightly. Your setting should then be perfect for the current wind conditions you are sailing in.
Any questions?
Next session, I''ll talk about the jib telltales.
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