Its not the servo, the servo arm that comes in the kit is plastic & when it pulls the sails in the arm flexes, i have since knotted direct to the arm & its fine now but concern that same thing can happen when i pull the sails in more so wind.???
"I have since knotted direct to the arm"Not certain, but thinking that if you have tied the sheet direct to the arm you will have doubled the torque (pull) on the sails, but you have also halved the amount of sheet travel. This may mean you do not have enough travel to sheet right in (booms nearly parallel to boat centreline) as well as right out (booms nearly at right angle to boat centreline)
I would think standard double haul arrangement would be the setup you need - the line should run freely through the hole in the arm.... if not perhaps there are some sharp edges.... the twisting arm sound like bad news, this should not be happening if things are correctly adjusted.
Possible first adjustment for your winch setup may be:
1) disconnect the sheets from the booms
2) then move the winch to the close hauled position,
3) then tie off the sheets at that point with the booms parallel to boat centreline
That should establish the close haul position. Moving the servo to the other end of its travel should allow the booms to be about at right angles to the centreline.
Hope this helps....