Abstract: A musical instrument string winder designed for faster tightening or loosening of a guitar key or similar that utilizes a planetary gear drive includes a handle housing with a protruding key socket near its periphery to accept a guitar key. The key socket has a recess for engaging a guitar key on one end and an integral planet gear on another end. The handle has a gripping portion one end and a relatively large integral ring gear on another end. The key socket planet gear has a predetermined diameter which is notably less than the diameter of the ring gear to afford it orbital movement around the ring gear. The key socket planet gear rotates on its own axis, subject to its position along the ring gear and is mated to a connecting element that is rotatably mounted to the center of the handle housing.