Sail trimming for a numpty

[NickSki]

G'day all,

 

I'm a social sailor, I'm mostly self taught and I haven't raced (but might start when I get a chance) or even a member of a club mainly because I'm in the military and work most weekends. Anyway, generally speaking, if I am running with the wind should I have the traveller right out (ie. full length of the rail) and most of the mainsheet out with the sail pushed against the stay and when I'm reaching is the traveller about half way out and the main sheet tightish? Or is it a bit more scientific/individual boat specific? When I'm running I struggle to stay about 30 degrees or so from the wind otherwise I have to hold the boom out as it gets eager to gybe. I've got a feeling this might be due to the rake I need to use on to stop the nose from ploughing but that is just a pluck in the dark. Also, the jib gets limp and seems pretty useless with the wind anywhere near behind me. When I was younger learning on monohulls as soon as the jib started to flutter you could pull it across to the opposite side to get extra sail area but with the mari it won't seem to do anything, even if I try to hold it out it just stays limp.

 

Is all normal? Any advice would be appreciated. Hope I haven't confused anyone with incorrect terms, I'm not very nautical apparently (as you could probably tell from my silly questions). 

 

Cheers

Nick

 

 

[QB2]

Enjoy your sailing and don't worry too much about the technical jargon .  But also just watch how your sail telltales work or stall out with different sail shapes on and off the wind.  Maricats are supposedly almost as fast straight downwind as tacking but i preferred to play with boat balance, heeling correctly to get drive and play with all ropes to adjust sail shape and angles to the wind rather than just be blown along. Running straight downwind let the mainsheet go almost out but retain some sail curve and also prevent wear n tear from the shrouds on sail batten pockets.  If you let the main just flattern against the shrouds you could hang any old rags up there to do the same thing. On a run If it is long enough pull the jib sheet out and around the rear windward shroud to help the jib stay out and working. In very light winds the jib will just hang there but keeping some shape in it will guarantee some effort going into movement.

 

Alternatively tack downwind and watch your telltales to let you know when both sails have good flow and are generating thrust.  You will feel the boat accelerate when you are '"in the groove'' and either sail up or downwind to keep them flowing and speed constant or highly technical term here, velocity-made-good,  VMG distance covered. . 

 

On a reach generally adjust the jib out so you get a nice curve and the leeward telltales work while the traveller also goes out and sheet in enough to get good sail shape (twist), airflow across it, lee telltales working ahead of the weather ones to generate power and boat speed. Loosen mainsail outhaul and the vang,or cunningham downhaul to make the main sail fuller.

 

Play with the traveller and/or mainsheet to maximise boat speed. Don't forget the slot between the jib and mainsail as if the jib is too tight or too loose it either spills the wind by stalling out or if too tight backwinds the main and reduces pressure. You have to play around in varying wind strengths and see what works and what doesn't on the various points of sail.

 

The most satisfying Mari racing i ever did was In a drifter ghosting from surface wind patch to patch where a keen eye and boat balance, sail shape and tactics got the crew and I a placing ahead of the flash and expensive toys of the go fast set who gave up.. 

[knobblyoldjimbo]

I'll have a go at this one!

 

1. You have a jib, this makes a difference.  Cat rigged Mari's are "blow downwind" boats (Frank Bethwaite) and do it just as quick as if they 'tacked' downwind (ie going on several fast reaches.  Sloop rigged Mari's (like yours) can go faster downwind if they tack. The trick is to keep the jib and main working all the time and steer down as low as you can go.  On the Cat boats the forestays are 5.5m and the shrouds are 5m.  See if your shrouds are 5m and that should indicate if you're in the right ballpark for mast rake.

 

2. Check out the tuning guide at the start of this group, that has some interesting tidbits.

 

3. QB talked about telltales.  If you don't have them these are bits of material that show the flow of the wind over the sails.  Ronstan sell them but you can make them.  I used bits of sail repair tape and nylon tape from a haberdashery (trouble was with them that they 'bled' colour onto the sail!) or nylon wool.  You cut about 150mm lengths and stick them to the sail about 1/3 of the way from the luff (on both sides of the sail).  If you put three on the jib and three on the main you're off to a good start.  On a reach the telltales should be flowing on both the windward and leeward side of the sail.  If you pull the sail too tight the windward telltale stops flowing and fly's upwards, if you let the sail out too far the leeward telltale flys upwards.  If you go directly down wind then the telltales are no use because there isn't a flow over the sail (it's acting as a big wall and also the jib will be pretty useless as it will be hidden behind the main).  Move a little to one side (onto a broad reach) and the telltales start flowing showing that there is flow over the sail (and it's now acting as a aerofoil - which is good).  Do the same for both main and jib and you should be moving pretty smartly along.

 

You can also have leech telltales.  These are ribbons that you stick to the leech (usually just the main).  They show that air is coming off the sail properly (straight back) or if you are causing eddies by pulling the main in too hard.

 

4. One more thing.  with the shrouds at 5m you may experience some weather helm going upwind especially.  This is where the rudders seem very strong and hard to keep the boat  from going head to wind.  We usually redrill the hole in the rudder to allow the blade to go forward of the centreline of the pintles.  If your rudder blade doesn't come forward a little (about an inch or less) then tell us and someone like Darcy will be able to tell you what the setting should be.  This makes steering much easier along with the raked rig which makes going upwind better and reduces the likelyhood of 'going down the mine' offwind.

 

5. We also put lengths of video tape on the forestays (cat rigged have two forestays) and I used to put one on the top of the mast.  This allows you to see where the wind is coming from.  If the boom is trying to gybe then you may be sailing 'by the lee' rather than directly downwind.  Some of us also used to have a big bit of elastic from the boom which we would attach to the end of the front beam (plastic hook) to hold the main out downwind.  You need to remember to take it off before gybing or going upwind (ask me how I know this!!).

 

6. Your point on going downwind is correct, you should be able to goosewing the jib but you might find that when you do the cat goes faster and the jib collapses.  Much better to bear up slightly and get the jib and main pulling with flow over them.  This is much faster for a sloop rigged cat.  If you watch 14ft cats racing you'll see them go around the windward mark, the sloops will roar off at an angle (reach) while the cats will go dead downwind.  Of course the sloops will get to the bottom mark first but then they have a faster handicap.

 

There's my tuppence.  Keep asking.  We all started at the beginning at one time or another.  

[korwich]

Jimbo on point 6

 

The sloop rigged boats will mainly tack downwind once there is enough wind to make it worthwhile, otherwise we would be just as wise to run square with the cat rigged boats with the jib goosewinged out to windward, there is nothing more frustrating than to have zig zagged your little heart out in wind that is marginal for tacking to use the apparent wind, only to meet the cat rigged boats that were behind you at the top mark are now rounding the bottom mark with you, they having had a nice relaxing square run from top to bottom, while you have stuffed about tacking all the way.

 

Conversly, if there is enough wind to make it worthwhile, we will tack downwind and as Jimbo says make the mark well in front of the cat rigged boats.  Deciding if there is enough wind is often a touch and go decision, that can win or loose a race.

 

Tell tales, I sailed mono's for many years before buying a cat, without ever knowing what the telltales were supposed to do or how to get them to work properly.  When I was a kid sailing a MJ we just sailed around with everything drum tight or ran downwind with everything out loose.  If we were heeling over than we had to be going fast right?  "Don't know what those ribbons on the sail are for".,,,,,,,,,

 

Phil

[korwich]

To sail a sloop rigged boat downwind tacking to the apparent wind you will definitely need to have some sort of wind indicator, be it one of those expensive arrow on a stick jobs or even just the video tape streamers tied to your fore bridle. 

You use the indicator to judge when the apparent wind is coming across your boat at right angles to the direction the boat is heading, if the indicator starts to tell you the wind has moved forward of your boat, bear off with your rudders, away from the wind till the indicator is at right angles again to your direction of travel (ie it is pointing directly across the boat).  If the indicator shows you that the wind has moved behind your boat, you need to head up, towards the wind to get your indicator at right angles to the direction of travel again.  (We know that the fastest point of sailing is on a reach with the wind coming in at right angles to the boat, right?)

This will not be a constant setting for you, you will speed up as you head up, thereby increasing the apparent wind, (apparent wind increases, the indicator shows the wind is coming more from in front) then you bear off to compensate for this change of wind direction, and will most likely slow down again, (apparent wind decreases the indicator shows the wind is coming more from behind).  Going downwind on each tack should resemble a somewhat regular weave up and down as you head up, to build up speed then drop off to head for the mark, slow down a bit, head up for speed, drop off toward the mark, head up for speed, drop off toward the mark etc.

 

Where abouts do you sail anyway Nick?

[knobblyoldjimbo]

Actually isn't it a bit more complicated than that Phil, you want the apparent wind to be forward as much as possible all the time.  Best example would be the Americas Cup cats, pretty much all the time their wing was pulled in tight (although they would have been constantly changing the rig, hence the puffing, sweating grinders who had to constantly keep the hydraulic pressure up for the trimming).  What always beats me is how they (and Phil in his sloop) manage to keep the apparent wind at the right setting all the time.

 

I would think that (given the right wind pressure) that the apparent should be closer to the front all the time, bear away as much as possible and come up just before the apparent lets go and the true wind comes in.  Thankfully in cat rigged boats this doesn't work so I can just point towards the bottom mark.

 

At the last open cat regatta at Manno where on the Saturday it blowing quite hard I rounded the top mark just after the guy from Rohan's club who had one of his nice new sails - he went high to tack downwind, I went straight down.  We met back at the mark, me just in front.

 

In light breeze at Toukley one year, Warren (Windrush sloop) went straight downwind while his son (same setup) went tacking downwind.  They met at the mark!

[QB2]

Nick if you have a local club go and introduce yourself and see if there is a similar sized cat there you can sail with and against or even just talk to sailors about their craft and what works for them. Its amazing how two boats can just sail together and the next thing you have a drag match race.. its a terrific way to learn how minor adjustments can make a difference.  Above all else enjoy yourself

[korwich]

Nick I second QB2

go to your local club, see if they have something similar to sail against, most clubs have a casual race fee, usually $10, just go out for the day and see how you go against the other boats, or what I find is really good, see if you can go out in the start or rescue boat and watch, I find I always learn a stack just being able to watch everyone, to see what the top guns do, and what the back of the fleet does different and how what the guns are doing makes them better/quicker.  After the race, go and ask the guns why they did what they did, (it helps if you are quick to give a hand to pull the boats out too, dont just stand there like a stale bottle of pi_ _).

 

Oh and going downwind in light conditions, get the weight forward and get the transoms out of the water and the nose down.  Trim the boat back as the wind increases, aim to sail downwind with the nose as close to nose diving as you dare.  It seems to work for Mick, except when he does nose dive, but I suppose nothing ventured nothing gained.

 

Phil

[korwich]

 

As you can see here, 2 cat rigged mari's at the schoolboys regatta at Belmont.  Sailing off the wind, weight well forward, with the transoms out of the water, almost textbook downwind light weather boat trimming.

[NickSki]

Cheers everyone.

 

Some very useful information here. 

 

I'm south of Brisbane so Humpybong would probably be the most appropriate club to look at. 

 

Thanks for the help.