twist, acceleration and speed

Submitted by frank barbehenn on Fri, 12/02/2005 - 14:48
I am a couple seasons into learning to sail the Scot (and a Catalina). I have read a great deal, but I still do not understand more precisely what I think authors are saying. My guess is that I am misunderstanding so I would like your help. For pointing, it seems that the mainsail top batten chord should be parallel to the centerline boom position, or even turning a bit windward by a few degrees. However, doesn't that then cause the upper sail to not twist with the upward twist in the apparent wind direction, given the apparent wind at the top is greater in speed and therefore angled a bit more to the side of the boat? Why would we want to lose that ability of the upper sail to drive the boat? Why not twist it to match the twist of the wind to maximize the speed while pointing in the same direction? I do not understand how you gain from that. One author I read also said that you never sacrifice speed for pointing, but even he recommends sailing with the upper batten chord parallel to centerline (vs angled out 5-10 degrees). I also do not understand what authors mean when they say that you can increase acceleration by easing the main but you won't increase speed windward. I don't get it. If you accelerate you have to be going faster!! Any advice from the Scot peanut gallery here would be greatly appreciated!!! Frank
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Comments

Frank, I am certainly not in a position to claim any expertise,

Submitted by chet.ensign on Sat, 12/03/2005 - 13:55.
Frank, I am certainly not in a position to claim any expertise, but I can tell you what has worked well for me the past couple of seasons. First, everything on my Scot is probably looser than it ought to be. Yet with rigging a tad too loose for the snug rig (I think), wrinkles radiating away out from the luff, crows feet on the jib, you name it, I point as high as other Scots in our area and match them with speed. In fact, we also have Jet 14's at our lake and I point as high and sail a tad faster than them under the right conditions as well. I think the Scot just likes it loose! The advice I have been given & follow is "keep the ribbon on the batten flying ~ 70% of the time. That, and keeping the batten more or less aligned with the boom under most conditions, seems to keep me moving just fine. As far as fast vs. pointing, what you are really trying to achieve is maximum velocity made good towards the mark. Straight line speed is just one component of that. You can go real fast on a broad reach but you are not moving upwind at all! Each boat has a point where its velocity towards the windward mark is at its maximum. You can point higher, but the tradeoff is that you loose speed. Under most conditions, heading upwind, I keep just the slightest hint of a curve to the jib foot, trim the main for the tell tale and boom / batten alignment and then concentrate on keeping the jib tell tales flowing and the boat in the groove. In races towards the end of the summer, I was probably sailing around 3 - 5 degrees lower than other boats in the fleet, but I picked them off on the upwind legs. Like I say, I am not an expert but any means, but that is what has worked for me. Best regards, Chet Ensign Fleet 184

quote:[i]Originally posted by frank barbehenn[/i] [br]For pointi

Submitted by Cole351 on Thu, 12/29/2005 - 00:25.
quote:
[i]Originally posted by frank barbehenn[/i] [br]For pointing, it seems that the mainsail top batten chord should be parallel to the centerline boom position, or even turning a bit windward by a few degrees.
"degrees" and "windward" - too strong for my taste... you should really think about tuning it down a bit. [url="http://www.hotels-all-over-the-world.com/portugal-hotels.html"]Portugal hotels [/url] - [url="http://gaming-online-poker-true.lavoa.com"]pai gow online poker[/url]