Prototyping: Donation Mechanism Money Drop

I built this little contraption to test the weight limit of the stepper motor. My donation box will accept bills and coins so I need to know if the motor can hold position when multiple coins are added. This stepper motor and pulley system allows me to move the axis of rotation to the center of the box which is critical since the lid will need to tilt inside the acrylic canister with very little tolerance for forward / backward movement.