ORIGINAL: ScaleME
Is there a proper location for the pivot point of the wash out angle along the cord of the tip airfoil -
LE, 25%, midpoint, TE?
IMO, you should pivot the tip at the trailing edge. I always use the F-16 and other modern fighters as examples.
The F-16 has a noticable amount of washout, but when viewed from behind, the wing has no dihedral.
If you washout anywhere but the trailing edge, you induce a small amount of dihedral as ZAGNUT has pointed out.
Dan