Lasco's core drills are designed to be used in a standard drill press. We recommend that you run your drill press between 750rpm - 1500rpm. Always use water or other coolant when drilling. For optimum results, drill under water, using an oscillating (up/down) motion. This will allow the water to get down into the hole. (Example: Cut 5-10 seconds, pull the bit back out of the hole, the water refills the hole, resume cutting. Repeat the process until your hole is cut.) Use light pressure.  Let the bit do the cutting. Place a piece of clay or wood on the back side of the object you are trying to drill. This will reduce chipping and/or fracturing at the exit hole. The life span of a core drill is impossible to predict. It varies based on the hardness and thickness of the material being drilled, and the skill of the operator. Remember that it is heat that is the enemy. Be patient, use light pressure, lots of water, and slow speed.