Review on Topec Diamond Drilling Granite Concrete by Chris Cruz

I mounted a hole on an angle grinder and made a perfect hole in a large river pebble. 1-3/8" is suitable for some tea lights, 1-5/8" is suitable for all. The cobblestones were gneiss, a little harder than granite. The bit cuts a perfect hole in the quartz crystal (much softer than granite) that I used for my garden LED lighting. The indicator says it's wet/dry. I cut out a lot of hard rock. So if you want to dry cut expensive holes, be my guest. I would never try to cut without running water. I want expensive bits and holes to last longer than a pit. As advertised. The epoxy diamond chips should last a while if you control the temperature. Diamond drilling is slow cutting. Let the beat work, no downforce and certainly no high speed. As advertised.