Your links should be behind the hinge line so you have an effect called ackerman (not sure how you spell it). If it is correctly done the cables will be tight with your surface centered and they will be a little bit loose when you move the surface to one side. It is not important that they are a little bit loose when the surfaces are deflected because the air will keep them in position, and it is more important that they are tight when the surface is centered. If you do it the wrong way and you put the links in front of the hinge line the effect is opposite, so your surface will be loose when it is centered.