Sounds like the arms are binding. Ream out the hinge pin holes, and take a little off the arms because sometimes they are tight fitting.
Sand off the black paint then polish the pins with Mothers Metal Polish.
I always do this on cheap hinge pins typically like the ones found in rtr kits. I don't see the need anymore to spend 60 dollars on hinge pin sets when you can polish up the cheap ones. Works for me.
Last edited by gashuffer; 05-31-2011 at 11:27 AM.