If you do not stick the L shaped part of the pin into either surface, it will come out in flight and you will re-kit your plane. I've been using them for years and love them. I usually put them into the wing or stab vice the control surface - no particular reason - at the same time I exoxy the hinge into the plane. I also coat the pins and hinge lines with petroleum jelly (but not the L that sticks into the wood) when I put them together to keep the epoxy from sticking to them .

Lynn