Worked very well for me. I had to drill a hole in the marble for a washing machine drain in the 2nd floor laundry room. I used 3M tape to create a small barrier to hold back the water. Water to keep the blade cool while spinning. I changed the water regularly as it became cloudy from the marble and the cut line was not visible. Start at a corner and finally align the cutting plane. The most important suggestion: take your time. Hold the drill in place with both hands.