Do you suffer from the "we.ve finished building the robot, so let's add controls" syndrome ?
We have arms that rotate about 225 degrees, but they are mounted on a gear, so gearing it was easy. Unfortunately, the smallest meshing gear had too many teeth to allow more than about 4 turns of the ten-turn pot. Works ok though.
Al is right about leaving some leeway, though. When adjusting your system, there is nothing nicer than not having a motor drive the arm past the end of the pot's rotation, so the pot doesn't need emergancy replacement.
