ORIGINAL: quentinmayberry
Thanks for all your inputs guys, I will re design the pivot and make sure it is on the aerofoil centreline and 25% forward of the MAC
Good idea to put it on the centerline.
To help a bit with the terminology, you actually wish to place the pivot at a location that is at 25% of the MAC. Designers figure out where the MAC lines up relative to the centerline of the surface and then measure back 25% of the MAC's chord. That would be 25% back from the LE of the chord of where the MAC would be if it were projected to be at the center of the span.