ORIGINAL: rlipsett
I heard that drawing a line in white crayon will prevent the ca from wicking into the portion of the hinge that has the line on it. This would be good for prventing the hinge line from getting stiff.
CA hinges are designed to get CA in them and still flex. After the CA sets give the surface a couple of moves back and forth and the hinge line will be freed up so that it has plenty of flex in it. Drawing with crayon on the hinge has no effect to keep the CA out because the CA will just wick up under the wax from the crayon.
Ken