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Don Guillette
12-20-2001, 06:17 am
POP QUIZ Here is a short pop quiz I give at the beginning of sail trim seminars I conduct in So Ca. It's a fun exercise and participants are given 3 minutes to answer the questions. What settings would you use for the following sail trim controls if you were sailing to windward in 1 to 3 knots of wind? 1)Traveler - where is it placed on the track? 2)Mainsheet - how much tension and why? 3)Halyard - how much tension and why? 4)Outhaul - how much tension and why? 5)Cunningham - how much tension? 6)Vang - how much tension and what else could you do to help your sails shape? 7)Draft Depth - what %? 8)Draft Position - what position on the boom (30% thru 60%) 9)Telltales - what are the leech and center ones suppose to be doing? 10)Mast Bend - how much? 11)Batten - where should top batten be pointing? 12)Leechline - how much tension? 13)Crew Position - what side and where on the boat (forward or aft)? 14)Twist - how much? Have some fun with this test. See where you stand from a sail trim knowledge standpoint. I'll publish the answers, which come from the likes of Dennis Conners, Gary jobson, Steve Colgate, North Sails and over 50 various writers in sailing magazines, in a few days. You'd be amazed at the different answers I get when I give this quiz!!

Gary Wyngarden
12-20-2001, 06:36 am
Sailing to windward in one to three knots of wind would for me be done under the iron genny! I'm anxious to read the replies however. Gary Wyngarden S/V Shibumi H335

henkmeuzelaar
12-20-2001, 08:33 pm
At least that would be so for longer passages with our Legend 43. So I,m with Gary's iron genny (as much as I hate that solution). Why not add 5 knots, or so, to make it more realistic? Flying Dutchman

Don Guillette
12-21-2001, 12:14 am
I picked 1 to 3 knots because if you can sail in that type of wind, you can sail in any conditions. One answer we all think about is to turn on the engine. I turn on the engine frequently, especially if I'm trying to get some where, but what happens if the engine fails us and we are in a tough spot. Wouldn't it be nice to know that you could "efficiently" sail your way out of the situation. If you intend to do any type of racing (anytime you meet another boat on the water, its a race), light wind is always a factor. When I publish the answers in a few days you'll see how easy it is. It is easy to know WHAT to do but more important to know WHY your making a particular sail trim change. Once you know the WHY, your miles ahead of 75% of the sailors worldwide. Check out the "Sail Trim Chart" sold in the Sailboatowners.com ships store. It lists all the sail trim controls for your main and jib and gives you the adjustment you need to make for every wind condidtion and point of sail. Additionally, the "Sail Trim Users Guide" also sold in the ships store, tell you why your making a particular change.

Rob
12-21-2001, 01:57 am
For the record, I am not speaking from the pulpit of authority - just interested in honing my skills and finding out what I know/don't know. 1)Traveler - where is it placed on the track? - CENTERED 2)Mainsheet - how much tension and why? LOWER TENSION TO ALLOW FOR BAGGY MAIN 3)Halyard - how much tension and why? LOW TENSION FOR FAT BELLY AND SMOOTH LUFF 4)Outhaul - how much tension and why? LOW TENSION AGAIN, FOR FULL SAIL 5)Cunningham - how much tension? MEDIUM, OR IN CONCERT WITH MAIN HALYARD 6)Vang - how much tension and what else could you do to help your sails shape? TESNSION LUFF UNTIL WRINLES ARE OUT OF LUFF AREA AND ROACH COMES INTO ALIGN 7)Draft Depth - what %? DONT KNOW 8)Draft Position - what position on the boom (30% thru 60%) 50% 9)Telltales - what are the leech and center ones suppose to be doing? OUTBOARD TRAILING BACK SLIGHTLY, INBOARD PRETTY MUCH HANGING 10)Mast Bend - how much? NO BACKSTAY ADJUSTER ON MY BOAT 11)Batten - where should top batten be pointing? ??? 12)Leechline - how much tension? ENOUGH TO STOP FLOGGING 13)Crew Position - what side and where on the boat (forward or aft)? CREW FORWARD, ON BOTH RAILS (centered) 14)Twist - how much? AS LITTLE AS POSSIBLE!

Kevin
12-21-2001, 04:40 am
I made the following assumptions; New main sail, mast head rig, no waves. 1)Traveler - set to wind enough so boom is at center line of boat. 2)Mainsheet - tensioned consistent with attached air flow, leech tell tails streaming aft. 3)Halyard - loose to increase draft. 4)Outhaul - loose to maintain bottom 1/3 draft 5)Cunningham - very loose to zero, some speed wrinkles are ok. 6)Vang - Depends, sometimes I use the topping lift to help sail shape. 7)Draft Depth - 15 to 17% depend on draft stripe postion. I used ascending order. 8)Draft Position - 45% 9)Telltales - steaming aft, parallel to sail. 10)Mast Bend - enough to support draft of 15 to 17% 11)Batten - parallel to boom 12)Leechline - loose to the point of no flutter 13)Crew Position - mid boat / downwind rail. 14)Twist- see #2

Jim Sullivan
12-23-2001, 07:11 pm
Submitted by Don Guillette of Long Beach, Ca on 12/20 at 02:17PM regarding sailboat 30. POP QUIZ Here is a short pop quiz I give at the beginning of sail trim seminars I conduct in So Ca. It's a fun exercise and participants are given 3 minutes to answer the questions. What settings would you use for the following sail trim controls if you were sailing to windward in 1 to 3 knots of wind? Hey Don !!! Another novice try.... My answers: In this light air maintaining some boatspeed is essential, hopefully in a direction which we want to go. Mainsail trim should be monitored regularly to be sure whether the sail luffs all the way up at about the same time and pulled in only until luffing stops. 1) Traveler - where is it placed on the track? ans: Midship so I don’t have to move it when I tack!... Lazy huh? 2) Mainsheet - how much tension and why? ans: Slack slightly footing the main off a little to add power and drive in the direction I am going. 3) Halyard - how much tension and why? ans: Slacked slightly to try to keep good mainsail shape and lift and power in the main. 4) Outhaul - how much tension and why? ans: Slacked. (see ans to 3) 5) Cunningham - how much tension? ans: None. 6) Vang - how much tension and what else could you do to help your sails shape? ans: Balance vang/toplift will align top batten and boom and simulate reasonable trim. 7) Draft Depth - what %? ans: Depends on cut of the sail. As much as you can get. 8) Draft Position -ans: what position on the boom (30% thru 60%) 50% 9) Telltales - what are the leech and center ones suppose to be doing? ans: Don’t use ‘em.. 10) Mast Bend - how much? ans: None. 11) Batten - where should top batten be pointing? ans: In line with the boom. 12) Leechline - how much tension? ans: None 13) Crew Position - what side and where on the boat (forward or aft)? ans: On my own boat crew will be positioned forward to leeward trying to heel the boat as much as possible seeking gravity help in shaping the sails. 14) Twist - how much? ans: None needed in this light air. Thanks Don I did have fun with this test... Jim < Why Knot!! >

Don Guillette
12-26-2001, 08:58 am
As those that have read my stuff are aware, I'm more into WHY we are making a particular sail trim adjustment then simply telling a sailor WHAT change to make. The following information has been gathered from the likes of Dennis Conners, Gary Jobson, Steve Colgate and numerous sailing articles on the subject of light air sailing. In very light air (under 3 knots), a flat sail is necessary because the wind does not have the power to get around a sail that has any amount of draft depth (belly). It is as simple as that but I always see fellow sailors trying to add depth to their sail and probably wondering why they are not getting anywhere. Your sail trim adjustments in very light air should be directed to the end of making your sail as flat as possible. Additionally, given the choice between speed and pointing, always go for speed (what little there is of it) over pointing. In light air (3 to 6 knots), the crew should be inboard and you should foot off slightly. This type of sailing is a sail trim balancing act, so ease the sail slightly to try and build speed. When you've reached max speed, try to point but don't push it. Get all telltales flying. Here's some problems you'll have to deal with - an over- trimmed sail and wide angle of attack will stall the sail as will a tight leech. Another problem is that a deep sail won't hold the wind flow. So, what do you do? Experiment and get the depth you need with a sufficient amount of twist but not enough twist so that power is spilled from the top of the sail. Here are the quiz answers : (masthead rig with half way decent sails) Traveler - Where is it placed on the track? Answer - Slightly windward of center. Mainsheet - How much tension and why? Answer - Ease sheet to obtain sufficient (not a lot) of twist. Halyard - How much tension and why? Answer - Ease because draft position needs to be aft. Outhaul - How much tension and why? Answer - Ease slightly from max because you want a slightly fuller bottom. Cunningham - How much tension? Answer - No tension. If you tighten the Cunningham you'll put back the tension in the luff that you just let off by easing the halyard. Vang - How much tension and what else could you do to help shape your sail? Answer - No tension and you could use the topping lift to pull up the boom,which would put a very slight belly in the sail. Draft depth (belly) - What %? Answer - 10% to 14%, which is a flat sail. Draft Position - What position on the boom (30% - 60%)? Answer - 50% or slightly farther aft but no more than 55%. Telltails - What are the leech and center telltails suppose to be doing? Answer - Top leech should just begin to flow. If it disappear,the sheet is too tight. Center telltails, which are located in the middle of mainsail (one on each side) should be flowing. Mast bend - How much? Answer - None, mast is straight. If you bend the mast you'll put belly into the sail. Batten - Where should the top batten be pointing? Answer - It should be parallel to the boom but can point slightly to weather. Leechline - How much tension? Answer - Tight Crew position - What side and where on the boat? Answer - Leeward and forward. Twist - How much? Answer - Minimum because the more twist you induce , the more power you lose. I hope you got something out of this quiz. If your confused about draft depth or draft position, please review some of my earlier articles on those subjects. As I've said before, if you understand the principals of draft depth, draft position, twist and angle of attack, you know more than 75% of the sailors worldwide and your also very close to seeing the total picture of what sail trim is all about. Next time your sailing in light air (under 3 knots) try the settings I've suggested and see if they work for you.

Rob
12-26-2001, 12:52 pm
It is one thing to read about sail trim, and another to actually discuss it (albeit over the net) with an authority. I never would have thought to flatten the sail, but what you say makes perfect sense - I can see the air just whirling and swirling over the top half of the sail's foil - resulting in a stall. Never thought I'd say this, but I am actually looking forward to my next light air day! Best Regards, (and thanks again) Rob

Brad
12-28-2001, 11:08 am
Hi Don...In your pop-quiz answers, you stated a goal of flat sailtrim. On mast bend, you state "none." I thought that mast bend is a major tool for flattening, as material is pulled out of the sails, so I'm a bit puzzled. As for the rest of your tips for light air, it was good to see some things I've been using confirmed by a pro. Great forum, which I hope to see expand...great job! Thanks, Brad

Rob
12-28-2001, 03:27 pm
Wow - what fun! Wind was 2-5 mph today, same conditions as quiz. Flattened main, moved traveler over to windward of center. Boat moved surely and constantly thought the water. I often wondered how some guys kept their boats moving in light air. It often seemed like they were creating their own wind. Today, I was one of those guys! Blew away a few boats, including one of my own class. Too much fun! Thanks Don! Rob

Don Guillette
01-04-2002, 05:10 am
Brad: You are correct that mast bend is a major tool for flattening the sail. The answer I gave has an incorrect portion to it. I got ahead of myself the day I wrote the answers as I was hurrying to leave for Lake Havasu, AZ to test, of all things for a sailor, a high speed jet race boat engine, which is developed by a friend of mine. I used to be heavily involved with jet boats, before I got back into sailing. Anyway, when I got to Barstow, I was thinking about the quiz answers (it is a long drive to the Colorado River and you have a lot of time to think about things) and my error hit me but it was too late to do anything about it. I was afraid a bunch of people would pick up on it. The reason you want the mast straight is that you want a little draft depth (belly) in the sail because belly (just a little) is what provides power. The mistake was, I said if you bend the mast you PUT belly into the sail. Actually, as you say, if you bend the mast, you ELIMINATE the belly. This may be of interest to forum participants as some sailors have a problem understanding this mast bend concept. It took me a while to get it as it didn't make sense, but try this experiment and you'll see what I mean. Pretend your index finger is your mast. Bend your index finger and see what happens to your knuckle. Your finger now looks like a backward "C". If your finger was the mast, see how it would pull the middle of the sail forward, thus flattening the sail. Sorry about the misinformation I put out on mast bend.

Brad
01-05-2002, 02:38 pm
Thanks for clearing that up. At the risk of jumping ahead, hope you can help on a downwind question that's been bugging me...I've got a H25.5 with sweptback spreaders and use a whisker pole. It seems easing the main is limited by the spreader angle, so say in moderate winds,what would you recommend as the fastest angles and trim downwind? Are there any sources of downwind/whisker pole info you'd recommend? Thanks again, Don...and it must be some adjustment going from 6 knots in a sailboat to 60 in a speedboat!

Don Guillette
01-08-2002, 12:17 am
Brad: Forespar has a great brochure on downwind, which I think you can get from West Marine. Also, if you can go to <http://kindred-spirit.net> and see an 11 page artical I wrote on the subjuct. Look for "Don Guillette's Downwind Stratagy" or something close to that wording. It is all the info I could find on the subject of downwind, of which there is really not a lot written. The course you sail downwind depends on a number of factors but the slowest way, which most people use, is dead down wind. After you review the article, if you have any questions, just fire away.

James rohr
03-06-2002, 01:24 am
#1 about 3-4" windward #2Just enougth to shape #3 Just enough to take out the wrinkles in luff #4 just enough to get bottom of sail smooth You don't want the depth to be to deep and loose attached flow. #5 none #6 none #7 not sure about % but med to flat #8 50% #9 All leech telltales should be flowing straight back #10 none ,you dont want to pull the draftforward in sail #11 Parrallel to boom #12 loose in that light air it won't flog #13 center all on leeward side and very quiet,very little movement. #14 none