In such applications, the metal drill movement follows a sequence similar to the beak-movement of a woodcutter bird(while it pecks the wood) i.e. the drill touches the job, drills a hole (of certain settable distance), is raised slightly and then repeats to drill the next set length. This sequence is a must, else the drill can break and the fragments can get stuck inside the hole, thus ruining your job.
This control over the drill movement is easily possible on Orion Wood Pecking control panel. This is a ball-screw and stepper motor based actuating system on which the mechanical drill is mounted. With adjustable user parameters on the controller, such a oscillating vertical movement is achieved. Complete package system can be offered here, along with AC drives for spindle motor.