Quantum Sails STAR, Tuning Manual

S TA R  /  T UNIN G  GUIDE

MAINSAIL

The mainsheet control is the most important control on the boat. The 
mainsheet is something you should be adjusting constantly whenever 
there is a change in wind velocity and water conditions and based on the 
mode of the boat or when making a maneuver. Be sure to experiment to 
find that right degree of trim for the day. 

OUTHAUL

The outhaul should have a range of adjustments from the foot of the 
sail touching the boom to about 8” off the boom for downwind. This will 
give you a range for any condition and point of sail. The best guide for 
the outhaul upwind is from 0-4 knots; the outhaul should be snug to the 
boom. when you’re in 6-8 knots of air and trying to generate power to 
hike against, ease your outhaul up to 1½”. In over 10 knots of air, tighten 
the outhaul to flatten the sail and reduce power.

Downwind, the outhaul should be eased to make the sail full. Ease it so 
that the shelf foot opens. 

CUNNINGHAM

The trick with the cunningham is not to overuse it. Leave some horizontal 
wrinkles in the main in conditions under 8 knots. Leaving these wrinkles 
gives the main the power it needs to get through the softer air. As the 
wind increases, use the cunningham to balance the boat. If the boat feels 
slow, ease the cunningham to return the power to the mainsail. On the 
downwinds, the cunningham should come off completely.

BACKSTAYS

The Star has upper and lower backstays. The upper is attached to the 
same spot as the headstay and helps tighten your forestay and depower 

TRIM GUIDE

your main, while the lower controls mast bend below the spreaders. 
Both backstays change the amount of headstay sag. In light air under 6 
knots, the backstays should be off or just snug. In over 6 knots of wind, 
the lower backstay should be loose or about 1” from slack. When the 
crew is just over the side, you want to pull on more lower backstay to 
generate more power. When it’s windy, you’ll want to ease the lower 
backstay to go faster forward. Tighten as needed to keep height and the 
main quiet in the biggest breeze. The lower backstay also controls the 
headstay sag and the slot between the jib and the mainsail. To reduce 
power in the sails, pull on more lowers, and to increase power, ease off 
the lower backstay. 

The upper backstay controls the upper part of the mainsail. This control 
is best used when the boat is overpowered. When the wind comes up, 
the lower is the first backstay to go on. When you need more balance or 
the boat is overpowered, the upper comes on to help flatten the boat. A 
tighter backstay will help the boat go lower and faster in heavy air, and a 
looser backstay will tend to make the boat point higher with less speed.
 
When reaching, the backstays should be eased to make the mast vertical 
to reduce the helm. 

When running, both backstays should be eased so that the mast can go 
forward. In light breeze, the backstay should be fully eased so the mast 
can get as far forward as possible. In heavy air, the backstay should be 
eased, but be careful not to go too far forward (more than 15”-20”) or the 
boat may become unstable. 

The crew should check the leech at the top batten to make sure it is not 
too tight. We define too tight as when the leech doesn’t move or is very 
tight. You will find that you need very little vang on a run. The rule is the 
same as trimming the leech upwind: Keep the aft end of the top batten 
parallel to the boom or looser.