Ceecrb1,

In the attached diagrams, note that the thicker portion of the airfoil makes the measurement off.

That is no problem for symmetrical airfoils, like the Edge’s, but it will be if trying centering throw deflections for cambered airfoils with the two sticks method.

For non-symmetrical airfoils, the central throw deflection is a continuation of the cambered central line of the airfoil.