Abstract: A collet release device for rotating the draw bar on a milling machine is disclosed. The device includes a pneumatically-driven impact wrench which can be lowered to engage and drive the draw bar in the desired direction. The structure of the device includes a frame which is mounted at the top of the milling machine near the drive head of the draw bar. A carriage, which supports the impact wrench, is slidably mounted on the frame and may be lowered by a pneumatic piston. A single control switch actuates both the impact wrench and the piston. Depressing a first button on the control switch causes the impact wrench to engage the draw bar and rotate in a first direction, while depressing a second button causes the wrench to engage the draw bar and rotate in the opposite direction.