mainsail trim

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May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Timm: I'm back home after almost 30 days on the road and seeing some of the most beautiful National Parks (Zion, Bryce, Capital Reef, Arches, Mesa Verde and Monument valley) that the western states have to offer. it was a fantastic trip and almost as relaxing as sailing but web and cell phone access is almost non existent in most of these places. My next big trip is in Oct. i'll be attending the Catalina 30 Nationals in San Francisco. This event is the high point of my sailing season. Our C30 National crew comes from all over the US to sail against the local C30 sailors. We pick up a loaner C30, which is sometimes a handicap, but we've been racing so long as a crew its not that bad. This year we will be using a boat out of Santa Cruz. We sailed the same boat to a 2nd out of 19 boats a couple of years ago in Santa Cruz in winds up to 40 knots!! What a kick that was. I hope to get a first in one of these National events before I'm too old to crank a mainsheet. Anyway, you can eliminate twist in the mainsail and jib on virtually all points of sail. The controls you use for the mainsail are the boom vang and mainsheet and as long as you can gain mechanical advantage from those two controls, you can crank out twist. Obviously, the farther out the boom goes the less mechanical advantage you get from the mainsheet (you start to pull the boom in instead of down) but you can still use the boom vang. On the jib, the twist control is the fairlead and the farther of closehaul you go, the fairlead losses its effectiveness from a twist standpoint. You can experiment and see what I mean. There is a method to my madness!! Why I picked closehaul to describe twist is that the problem I've found is that a lot of sailors have trouble visualizing twist no matter how hard I try to describe it but once they see it they don't forget it and it is easiest seen and controlled when closehauled. While sailing closehauled you can actually see it go in and out as you crank on the controls. Additionally, closehauled is the fastes point of sail and I want sailors to be able to get as much speed as they can out of their boats so twist control becomes most important because it is spilling power (speed) out of the top of the sail.
 

aigen

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Jun 5, 2004
2
- - hawaii
re: sail trim

hey, I'm into my first sailboat, a cape dory 27. As a true novice, I appreciate its traditionally simple yet durable reputation; it has no vang, I don't use a chute (yet), and electronics are minimal (tridata, radio, compass & windex). If you're familiar with this boat, I'd like your help on one item I'd like to master: the traveller. Exactly how, why and when is its adjustment necessary? K.I.S.S. Your replies are appreciated! steve
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Sail Trim

Steve: The traveler is only one of about 10 mainsail controls and they all have to work together to obtain good sail trim. First of all, lets define what the traveler does. It adjusts the ANGLE OF ATTACK. Angle of attack is one item of four, which I call the "the 4 elements of sail trim". The other 3 are DRAFT DEPTH, DRAFT POSITION and TWIST. Without going into a lot of detail as what the angle of attack is (you can check the archives)lets just suffice it to say that the more you move the traveler towards the center of the boat, while sailing closehauled, the faster the boat goes and if you ease it off, the boat will slow down. It all has to do with generating LIFT and lift is power. The traveler has very little to do with the actual trimming of your sails. Here's why - picture your screen door at home and assume there is a track on the floor and the edge of the screen door has a pin, which rides in the track. When you open and close the screen door does the shape of the screen change? Nope, it doesn't and that pin and track are just like the traveler on your boat. The next time your out sailing, get your sails set so your getting 100% efficiency and thus your boat is going at its best speed. Now just drop the traveler and watch what happens to your speed. So, if your ever in a position where the boat is excessively heeling and you want to gain control, first just drop your traveler and she'll come right back on her feet. Also, you want to play your traveler. In other words, if your sailing along and and you encounter a large puff of wind, just ease your traveler down. Converserly, if you encounter a lull, just move your traveler up toward the center. Right now, you know just about everything there is to know about the traveler and probably more than 75% of the sailors worldwide. If you don't believe me and to have a litttle fun, just ask one of your dock neighbors or sailing friends to describe the traveler to you and see the answers you get!!
 
Jun 4, 2004
12
- - Richmond
Twist

Okay, so I can set the twist on any point of sail as long as I use the "top batten parallel to boom" as a guide line.
 
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