Randy says don't do it
http://tinyurl.com/AnotherDizzyGearThread
i was hoping regardless of cost that polymer would be the Big Go in the dizzy gear dept but i think what it is they don't take shock very well. the material just doesn't have enough staytogetherness for the forces involved vs the limited mass of the gear shape. i know that it's definately recommended that you don't 'bump drop' a polymer gear by tapping the key or solenoid
there'll be phantoms, there'll be fires on the road... and the white man dancing