A medical device control handle has with a distal component which is adjustable by an actuator assembly by means of a puller member or wire. The actuator assembly includes a user interface rotational dial, a detent tab washer and a spool, where the dial is rotationally coupled to the detent tab washer which transmits rotational movement of the dial to the spool. The spool has a shaft body and a drum end onto which an proximal end portion of the puller member can be wound to manipulate or adjust the distal component. Rotational movement of the detent washer is limited to prevent overrotation and breakage of the puller member. At least one washer is mounted on the shaft body of the spool to help apply compression load on the actuator assembly in friction-inducing contact with one or more components of the actuator assembly.