Colinkites2000
Member
I wanted to get a new thread going on this because it no longer relates to the article by Ron I was looking for. What I am looking for is information on the mainsheet tension/mastbend/sailshape relationship (upwind) moving from sheeted out 6-8" (super light conditions) to 2 blocked. Continued below from the other thread.
Thanks for the info here. I am pretty clear on the effects of the vang/cunningham as you start to use them more in mediun/strong winds. The part that I was/am unsure about is in lighter conditions going from sheeted out to ensure flow, to sheeting in to increase return - as the breeze picks up a little. I got the impression from the laser tuning guide that when you sheet in to two blocked, the mast bends and therefore opens the leech-- (comments from the guide below)
"As a result, as the Laser mainsheet is pulled tighter, bending the mast and flattening the sail, it reduces leech/batten hook or "return" and opens the leach."
and
"Conversely, easing the Laser mainsheet makes the sail fuller, causing more return in the leech and adding power."
George says that when the sheet is pulled tighter, it closes the leech and therefore this would offer more return if you could ensure flow... but the tuning guide implies that if you want maximum return, you would ease the sheet so that mast is straight and pulling the sheet in further will only reduce return and open the leech.
Other advice states that as soon as you can ensure flow, it is ideal to be two blocked for maximum return- as George implies. Maybe once there is a little power in the sail when the mast is straight, you need to pull it in further just to keep the boom in towards the middle of the boat due to the load pushing sideways on the mast.... but to me with the information in the guide, it seems like sheeting in further would only reduce power when you are still not at hiking max.... thus hurting pointing ability.
Cheers
Colin
Thanks for the info here. I am pretty clear on the effects of the vang/cunningham as you start to use them more in mediun/strong winds. The part that I was/am unsure about is in lighter conditions going from sheeted out to ensure flow, to sheeting in to increase return - as the breeze picks up a little. I got the impression from the laser tuning guide that when you sheet in to two blocked, the mast bends and therefore opens the leech-- (comments from the guide below)
"As a result, as the Laser mainsheet is pulled tighter, bending the mast and flattening the sail, it reduces leech/batten hook or "return" and opens the leach."
and
"Conversely, easing the Laser mainsheet makes the sail fuller, causing more return in the leech and adding power."
George says that when the sheet is pulled tighter, it closes the leech and therefore this would offer more return if you could ensure flow... but the tuning guide implies that if you want maximum return, you would ease the sheet so that mast is straight and pulling the sheet in further will only reduce return and open the leech.
Other advice states that as soon as you can ensure flow, it is ideal to be two blocked for maximum return- as George implies. Maybe once there is a little power in the sail when the mast is straight, you need to pull it in further just to keep the boom in towards the middle of the boat due to the load pushing sideways on the mast.... but to me with the information in the guide, it seems like sheeting in further would only reduce power when you are still not at hiking max.... thus hurting pointing ability.
Cheers
Colin
181255 said:181255 -> Good comments George, I think it is also important to note that in that last picture they are probably sheeted out a litte. For sure tons of vang and cuningham, and totally working the boat in every single wave they see in front of them. The Locks is good for this type of sailing.