Any Questions?

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May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Shipmates: I'm not sure where to start the forum so I'll just throw this out. A couple of years ago I was pitching my sail trim seminar to a sailing club in Marina Del Ray, Ca. One of their members had asked me to make the presentation because he felt there was a sail trim void in the group and that they would enjoy their boats so much more if they knew how to sail them properly. Before I gave my pitch he told me that after the presentation, when I asked for questions, the members will just sit there and look at me. I've never forgotten the words he used to describe the situation - "a man does not know what he doesn't know!!". It means, most beginner to intermediate sailors do not know what questions to ask and that is exactly what happened - they just starred at me and there was dead silence. What I did then was reflect back to when I was the most confused sail trimmer in the world and feed them a few questions based on that. Amazingly, after I did that and I now do it all the time, the discussion took off. It was about an hour later before I was able to get out of the room. The club never did buy into the sail trim seminar. My friend told me that most of the club members are happy just to raise the main and roll out the jib and call it sailing. The boat does move through the water but your sail boat wants to give you so much more and you can't believe how simple good sail trim actually is when it is presently logically and, most importantly, in SIMPLE terms that even I can understand. So, with that in mind, here I am standing in front of you. Do you have any questions or should I start feeding them?
 
J

john

about that trim

I have had my Macgregor 26D for about a year and a half now. One nice day while out on the sound I had just my main up and doing quit well, or so I thought. While moving along at about 2 or 3 knots I noticed another sailor coming up behind me quite fast. As he over took me it made me wonder how he was going faster than me. We both had about the same size boats and just the main up, but he over took me and never looked back. Since then I have read all I kind find about how to the set the sails in relation to the wind and direction. Some time I hope I see that other boat again ....
 
Oct 7, 2004
106
Hunter 260 Abundance - H260, Las Vegas, NV
Sail Trim

John, How much wind was blowing? What was the angle of the wind to you at the time? Are you quite sure his motor wasn't running? I just sold my Mac D after 9 wonderful years with her. Great boat.
 
J

Jerry

Hunter 37 cutter

What are the differences between watching sail trim on the cutter rig versus the sloop. I notice that I only get a half a knot increase when using the staysail. Is that the average or should I be looking for more? Thanks in advance!
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
John: David may have the answer. A while back I was sailing from Long Beach to Dana Point at night with a group of friends. One of these guys is always "giving me a go at it" whenever he sees me on the water. Many times I bait him into it by purposely slowing down just to entice him. By the way, here's the reality of sailing. Anytime 2 boats meet on the water your racing whether you know it or not!!! Anyway, on this night I decided to mess with his head and when I got a bit ahead of him I kicked on the engine and motored at about 900 to 1000RPM - just enough to make a little headway. It drove him nuts. I liked watching him running all over his boat trying to squeeze some extra speed in order to catch me. At one point he called me on the radio and asked me if I was running the engine. I told him of course not. Later he asked me what I had done to get such good speed in light winds - better sail handling was my answer.
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Jerry: There is no difference between sail trim on a masthead or fractionalrig or a boat with a staysail - it is either right or wrong. My only experience with a stay sail was on a Newport30. We were racing this boat and trying to squeeze more speed out of it and the owner installed a staysail. When we deployed that sail the boat "jumped" ahead. I would say that the minimum increase should be 1/2 knot but I think if it is correctly trimmed you should be get over 1 knot increase in speed - maybe more. There are probably guys on this forum who can give you more input.
 
Jun 9, 2004
165
Hunter 37-cutter San Francisco Bay
More on staysails

What about the advantage, or disadvantage, of using the staysail upwind? Downwind? Beam? I have heard folks on this forum suggest it hurts more than helps downwind, and I've heard others say it helps by steering the wind into the jib?
 
W

william

Sail Trim is part of the equation

Here's a J-105 pulling away, I did a vanderbilt type start that is, headed opposite direction away from the start line- then timed myself- same time back so as to hit the starting line at full speed.
 

RichH

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Feb 14, 2005
4,773
Tayana 37 cutter; I20/M20 SCOWS Worton Creek, MD
Staysail trim

Upwind the staysail is a very difficult sail to get correct shape and only gives a 'teeny' bit of upwash advantage to the genoa. The difficulty in setting/shaping is due to the fact that the staysail when closehauled sits in between the genoa and the main where there is reduced flow. Most times (on a beat) when under a genoa it will have little apparent 'draw' - but thats entirely OK. What the staysail 'can' do when beating is to reduce the turbulance at the mast section - better mainsail flow results in better genoa flow. The set should be (usually) so that the entry section (luff) is well rounded (attained by hard halyard tension) and a flat shape back from there - tell-tales at mid cord and leech should be flying 'perfect' and the leech carefully shaped to match the shape of the genoa leech, etc. The result is a slight increase in speed, but a much better ability to sail closer to the wind (point) due to the 'upwash' on the genoa. Its a 'bitch' to properly set and shape when beating. So, when beating, using the staysail may not get you any extra speed but if trimmed/shaped correctly can help you 'point' better. Otherwise when reaching, when the staysail 'fills-in' the foretriangle - then staysail has significant advantage (especially if flown from a boom). Downwind the staysail will get shadowed by the main very easily .... and if flown from a boom, its time to fly it on the windward side with the boom prevented. On a broad reach and below, its ALWAYS easy to get too much twist ... much better if the boom has a vang or a means to secondarily sheet to the rail to control the adverse twist. Withouot a boom ----- there is almost NO way to control the twist. The Hoyt Boom is probably the best invention ever made for flying a staysail - keeps the twist constant. Otherwise below a broad reach most staysails are usually well overtrimmed on the foot and flappin' at the head --- tooooo much twist. THATS the DISADVANTAGE of a staysail - controlling the twist! The staysail is greatly misunderstood by most trim 'experts', and there is essentially NOTHING written that can help you - its all errant conjecture. The only correct aerodynamic analysis on staysails was done by Arvel Gentry the famous aerodynamicist/sailor - such (brief) work can be found in the compendium "The NEW Best of Sail Trim" (paperboack) by Sail Magazine in the early 90s. Sometimes specialty marine booksellers such as Sheridan House offers TNBOSTrim. Gentry's seminal articles on steering telltales and his method/technique of tell-tale usage are also in NBOST. There are other EASIER articles and publications such as by **Don Gillette** (anyone know him?) that have greatly simplified the usage of tell-tales to obtain the BEST set and shape. ;-)
 

RichH

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Feb 14, 2005
4,773
Tayana 37 cutter; I20/M20 SCOWS Worton Creek, MD
OK Don, Here's a question .......

How do you trim the mainsail when broad reaching down wind... and the telltales are slack because the sail isnt 'flying anymore' .... just dragging the wind? How do you determine how much draft to put in ... and the tell tales are 'hangin limp'? Sure, you can look at the knotmeter but thats not good enough..... how are you SURE you have the best set/shape? :)
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Rich: Great question and it opens up a lot of stuff for discussion, which I think will be of interest to a lot of sailors. First on the limp telltales – telltales only work because of what is called “attached flow”. Picture your sail in a wind tunnel with smoke blowing over it. Remember how the smoke sticks to both sides of the sail. That is attached flow. In the scenario we are discussing, there is no attached flow because the wind is pushing the sail so they just hang limp. The sail is stalled. There are a set of telltales that will help you on this point of sail and you should have them on the shrouds and back stay. I use the cheap stuff they use to tie up tomatoe plants!! Why it is sort of difficult to sail on this point of sail is that you have very few clues to guide you. On other points of sail you have weather helm and heeling, in addition to telltales, to provide sail trim adjustment information. So, the first thing to do is set your mainsail trim controls. Sailing to windward, everything was pretty much tight. On this point of sail we want almost all sail trim controls for the main loose. Loosen the outhaul almost all the way, which is providing depth and also loosen the Cunningham (halyard) and backstay. Keep the boom vang fairly tight as you do not want to over vang but you want to keep the boom from rising. A little twist in the main is OK. Next, tighten the leech cord, which bend the battens. The reason you want to loosen the Cunningham is less Cunningham moves the draft position aft and deepens the sail. More Cunningham does the opposite. At this point, we are ready to trim for speed. First drop the traveler down almost all the way. Now trim the mainsail in the following manner. Ease the mainsheet until the sail luffs and then trim it back in until the luffing just stops. This is called “trimming to a point of draw”. Now think back to what it was like to fly a kite as a kid because that is exactly what your mainsail is – a big kite. You flew the kite by FEEL and that is exactly how you fly the mainsail. I always keep my hand on the mainsheet at this point of sail because it is my kite string. I’m feeling the power in the sail Now what you have to do is experiment and find the optimum course for various wind speed because you boat does have an optimum speed and that is where the speedo comes in. Man, that was a long answer but I hope most of you got something out of it. Did I leave anything out or confuse anyone?
 
S

Swimmer Capri 25

New Sailor

I'm new to sailing having purchased my boat late last summer. I also sail on a lake which has a great deal of variable wind. I know you can't give me all the answers in this forum, but what would be best for me to concentrate on learning regarding trimming my sails in this set up. Swimmer is rigged with a 150 genny on a furler and a full batten main with a loose foot. Thanks.
 
May 17, 2004
2,111
Other Catalina 30 Tucson, AZ
Swimmer Capri 25: Actually, I can help you but your question is like asking a flight instructor at pilot ground school to teach you how to just to take off and land. You may as well learn all there is to know about sail trim and get it over with. Learning in bits and piece is counter productive. My answer is going to sound like a commercial but there is no other way around it. I have taught over 1000 students just about all there is to know about sail trim in 3 hours of intensive classroom training. Then, with about 1 hour of "on the water" application of what they learned in the classroom, I will stack these sailors up against 75% of the sailors worldwide any day of the week. So, your next question is when is the next seminar? Unfortunately, I have none scheduled on the horizon. The next best thing is my book, The SAIL TRIM USERS GUIDE,which is the text for the seminar. This book starts out with draft depth, draft position, twist and angle of attack, which I call "the 4 element of sail trim". If you do not understand those 4 terms, nothing about sail trim will make any sense. Then I discuss all the sail trim controls for the main and jib and tell you exactly what happens to the 4 elements of sail trim when you ease or trim the controls. The next part of the book deals with the settings for both the main and jib for every point of sail and wind condition. There is a lot more covered but that is a general idea. There is a companion to the book and it is the SAIL TRIM CHART. This chart outlines all the sail trim controls for the main and jib and gives you the setting for each point of sail and wind condition. It is laminated so you can take it on board with you. The Chart tells you WHAT to do and the book tells you WHY you are making a sail trim adjustment. After digesting and understanding the principles I outline and practicing them on the water, in a very short time you will not need either the book or chart anymore. Give them to a beginner sailor friend Sail trim appears confusing but it is not nuclear research. It is self limiting. In other words, once you get it down - there ain't no more. You just refine your technique. Give my good friends Karisa and Sara a call at the ship store at sailboatowners.com and ask them what other customers think of the my two product. They will give you an honest opinion. So Swimmer, I did not give you specifics but I hope I've at least sent you off in the proper direction. by the way, if you buy my products and are not completely satisfied, I'll refund your money and you can keep them!! If you weren't completely satisfied why would you want them but I just throw that in to show I'm a nice guy!!
 
W

Wayne Elphinstone

Down Wind performance

Great to have you back Don. I have been having trouble getting any speed downwind on my C380, I just read the artical you did on Downwind sailing and it all makes sense, I was sailing far to much directly downwind. Can't wait to get out there again. Regards Wayne
 
Mar 30, 2005
2
Hunter 35.5 Portsmouth UK
Mainsail Battens

Hi Don, I have a question regaring the effect of sail battens having had to replace all my main battens after a particularly "exciting" passage during which time I managed to loose all but the top batten to the sea gods. My boat is a 35.5 legend with fully battened main which I had to replace as stated. The problem I had was that I did not have any of the originals to use as a guide and the "sailmaker" was less than helpfull to say the least and would not recommend any kind of replacement and insisted I chose from a very limited range as replacemnts for the leg home. The net result is that I feel that the battens may be somewhat stiffer than the originals and I would like to know what effect I can expect on sail trim. Thanks in advance
 

RichH

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Feb 14, 2005
4,773
Tayana 37 cutter; I20/M20 SCOWS Worton Creek, MD
Take a look at the remaining original batten ....

Eudorajab -- Take a good look at the original batten .... What is the cross sectional shape? Square, pultruded (diamond shaped), etc.? Different shapes flex at different rates. Is the original tapered? ..... the portion of the batten towards the luff sanded to a fine taper? You can imitate/duplicate this taper with 220 sand paper and a palm sander, etc. How 'tight' does the batten fit into its pocket? and is there any adjustment for changing the compression along the long axis of the batten. For flat (speed) sail shapes near the luff the batten should be somewhat 'loose' in the pocket (less compression); conversely, if you want a more full (power) shape near the luff you want more compression load on the batten, etc. With more compression load (tighter in the pocket) the batten will behave very stiff and may actually 'pop' when the wind changes from one side to the opposite side, etc. ... in the extreme case if the axial compression is too great in especially light winds the sail may not even take the correct shape when the batten is 'too tight' and may be held in a 'reverse shape' ('cupped' to leeward). If the pocket doesnt have a means to adjust the tension, and you feel that there is too much compression, then simply start removing very small increments of batten length until you get the performance you want .... or buy similar battens as the original and reinstall. If you cut too much away, you can always add 'shims' to the batten ends - 'shims' are cut from polyethylene beverage bottles to make up any dimensional difference. When cutting battens dont get 'carried-away', just cut a small 'bit' at a time until you get the shape and performance you desire from the sail. ;-)
 
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