Mast position
The step position is a point that fundamentally changes the character (helm feeling) of the boat. Normally, the position where the mast is based on 1524 mm from the shear point of the bow.
PMJ has a marking line on the side of the mast step to serve as a guide.
Look for a place with a good feeling (moderate helm feeling) by moving it about ±20 mm from this marking line.
With the step pin in front:
･ Lee-helm becomes stronger (better speed less angle)
･ Bend decreases (= sail becomes deeper)
With the step pin behind:
・ Weather-helm becomes stronger (powerful feeling good angle)
･ Bend increases (= sail becomes shallow)
In the case of this boat, the Lee Helm is strong and I wanted a mast bend, so I put the mast about 10 mm behind the marking.
In addition, there is a distance between the front of the mast hole and the front of the mast as a guide for the position to stand the mast.
Many sailors tune the boat to make thes distance about 20 to 40 mm.
If this distance is too narrow, under strong wind condition and when the main sheet is trimmed hard and the mast bends, the mast will immediately hit the front of the mast hole.
This privents the mast to bend any further which can make the main sail not shallow enough.
This will make the boat difficult to sail without easing the main sheet.
Pay attention to the above two points and decide the position where the mast is set.
Front and rear position of side stay
The front and rear positions of the side stays tend to be preferred at the front.
The reason is that the front mounting position is closer to the mast, and this makes the mast stiffer against the pressure of the wind trying to bend snipes "soft mast" sideways.
In addition, if the mounting position is in front, the spreader will be pushed forward (= the mast will be pushed forward), making it easier to fore bend the mast.
On the contrary, if the mounting position is set to the back, the mast will be easy to side bend, it will be difficult to fore bend, and the mast will lie on the back side.
Spreader length
The spreader length affects the amount of bend and the ease of side bending of the mast.
It is about 420mm ~ 480mm.
long:
･ Push the mast forward and increase the bend (= the sail becomes shallower)
･ Overhanging sideways makes it difficult to bend sideways (= wind is hard to escape and becomes powerful)
short:
･ The amount of pushing out the mast is reduced and the bend is also reduced (= the sale becomes deeper).
･ There is less lateral overhang and it is easier to side bend (= it is easier to let the wind escape and it can be depowered)
There is also a method of stretching and powerful in light winds and short in strong winds to let the wind escape.
Snipe has a weaker tension than other boat types, so the lee side stay will slacken when going up wind. Then the weather side stay will push out the weather spreader and pushes the center of mast sideways. This is not good. Some players make the spreader relatively short to prevent this problem.
In this case, you may set the tension higher to compensate for the power and the amount of bend.
Prebend
Prebend is a point that directly affects the shape of the sail.
It's about 45mm ~
Deep sale has a lot of pre-bend,
Shallow sails reduce pre-bend.
Prebend changes due to various factors.
How to increase (decrease) prebend
･ Pull (ease) tension
･ Longer (shorter) spreader
･ Attach side stay to the front (attach to the back)
･ Mast step position to the back (to the front)
and so on.
Deflection
Snipe deflection affects the mast bend only in strong winds.
Normally, the screw at the base of the spreader does not hit the bracket. The screw hits the bracket only when the mast bends greatly due to strong wind pulling the main seat strongly or applying a bang, so that the mast does not bend any more. Will do it.
Mostly around 700mm.
If the main sail is wrinkled at a large angle in strong winds, or if the sail becomes fluffy, the mast may have overbent, so increase the deflection (= insert screws = earlier timing). Make sure that the screw hits the bracket = stop the bend early).
On the contrary, when the main sail is deep in strong wind and there is too much power, there is a possibility that the bend is not enough, so reduce the deflection (= pull out the screw = the screw does not hit the bracket easily = bend more) increase.
Tune with reference to the feeling when running in strong winds and the shape of the sail taken from behind.
rake
The rake affects the helm.
It is about 6500mm ~ 6580mm.
Lowering the rake will increase the weather helm,
If you raise it, it will decrease.
Applying this to the traveler seating ship, if the wind becomes strong and you cannot run, you can pin up and raise the rake without raising the side tension to reduce the weather helm and make it easier to run.
It is a part that is relatively easy to trim (it is easy to change the tuning) even while sailing, so if you feel something is wrong with the running load, you may try changing it positively.