Thanks AERORICH nicely said. Iv been in the hobby for a long time and Im also a pilot. Currently employed by the Air force as a avionics technician on the F-16. I know aeronautics and airfoils, but i didnt mean to bring up bernoulli's principle. Your absolutely right about not deforming the shape of a prop and I will back you up on any argument there. Im not confused about where I should remove or add weight to a prop. I just want some opinion on how often and how many people actually do it.