Sail setting

At a recent days coaching at Wilsonian SC there wasn't a lot of wind first thing. I made the most of the time on shore to look at sail setting using a Streaker and Laser 2000, this is the write up I produced after the day as I spouted quite a bit of complex information. Hopefully there are a few good bits in there that anyone can take something from.

Sail setting What each control does:

• Downhaul, adds tension to the front of the sail, flattening the sail and causing the leach to open towards the top of the sail. A very useful tool to depower the sail. It also pulls the centre of effort forwards in the sail.
• Outhaul, controls the shape towards the foot of the sail
• Kicker, Pulls the boom down, which will control the leach of the sail. Also pushes the boom into the mast causing the mast to bend, which has the effect of flattening the middle part of the sail, and moving the centre of effort rearwards. The angle of the kicker can give a good idea of which effect is likely to be more pronounced on a boat.

The streaker has a relatively low boom and kicker mounting point quite far back on the boom. When the kicker was pulled on the mast bend and consequent flattening of the sail was very noticeable, the effect on the leach was less so. If compared to a Laser 2000, one would find the kicker has a far greater effect on the leach as opposed to the mast bend as the kicker pulls the boom down to a greater extent.

·         The mainsheet: When pulling in the mainsheet, the last few inches will not only pull the boom in, but in the absence of significant kicker tension, will pull the boom down. This will effect the leach of the sail.

What to do in each wind strength?

Light winds: The ideal sail profile is relatively flat, so the the wind has the energy to flow around the curve of the sail. Be careful to leave the leach of the sail a little open to allow the wind to exit the sail. In light winds it is easy to tension the mainsheet too much hooking the leach, and causing turbulence at the back of the sail.

These pictures show different leach tensions, on the left the leach is very open, note how the back of the sail twists to leeward, on the right it is quite straight. The straight leach will give good pointing and is important in medium winds, but when the wind is light a slightly more open leach will give better speed.

A flater sail can be achieved by bending the mast slightly, kicker does this in most singlehanders. Spreaders will do the same job without affecting leach tension on boats with more sophisticated rigs.

Keep the outhaul fairly tight as well, any creases in the foot of the sail means too tight.

 

In medium winds when you are trying to gain maximum power from the rig, ease all controls. The leach of the sail should be kept tensioned using the mainsheet.

In strong winds progressively pull on more of each control to flatten the sail. The downhaul and kicker should be used together in most singlehanders to avoid the centre of effort moving too far back in the sail. These are your 2 main depowering controls. Pull the outhaul tight, but leave some shape in the foot of the sail as you need some drive.

Wind	Downhaul	Outhaul	Kicker
Light	0	some	Little, to bend mast
Medium	0	Loosest setting	Take up slack
Overpowered	Progressively more	Tighter	Pull on progressively
Very overpowered	Lots and lots	Bit tighter still	Tight