Marked the location of the holes with a square. Center punched the holes the same distance as the rods. Placed the base in a vise in the drill press and tightened in place using an angle gauge for position. Used a center drill, so as not to wander, then drilled starting with a smaller drill then what the center drill opening is. Since a properly sharpened drill will follow an existing hole the spacing was kept pretty close. I already had made the stone holder about a year ago. The SS rods on the stone holder are longer then ones you might purchase. This way I was able to use the extra length to fit in the base. One day was looking for a way to maintain the sharpening angle on the blade. I feel that this is easier then with the stone laying flat on the bench. I can use many different types and sizes of stones with this set-up. The one in the picture is a King combo 1000/6000 stone. Puts quite an edge on the knives. The material was scraps from my old place of employment. (retired) It has a high ware factor and I have used it for machine parts. I think it can be purchased from McMaster Carr Industrial Supply or MSC Supply. They have web sites. Didn't take long once I figured out what I wanted to do. I can add other angles to the base at any time. Everything is held very secure. When drilling non ferrous material you should remove the sharp cutting edge from the drill bit so as not to get hurt or ruin your work.