Image viewer stops?

rotating the crank scrolls the images based on angle of rotation.
the problem is that when i let go of the mouse, the crank stops and “sticks” and doesn’t work any more.
i want the images to change as the crank is cranked, and be able to keep cranking in both directions during and after.

any help would be appreciated :slight_smile:
fla is attached.
here is the code for the crank:

mc.btn.onPress = function(){
scrolling = true;
}
mc.btn.onmouseUp = function(){
scrolling = false;
}
onEnterFrame = function(){
if(scrolling){
var dx=mc._x-_xmouse;
var dy=mc._y-_ymouse;
var rad = Math.atan2(-dy,-dx);
var angle = (rad*180)/Math.PI;
mc._rotation=angle;

if (angle>85 && angle<=90) {

trace("angle = "+angle);
_root.changePhoto(1);
} else if (angle>175 && angle<=180) {
trace("angle = "+angle);
_root.changePhoto(-1);
}
}
}