CS Unitec DBE 201 8″ Capacity Concrete Core Drill – Wet Diamond Core Drilling Rig – For Concrete, Brick, Block, and Stone – MADE IN GERMANY – 110V

I have ordered the machine to drill holes in 6″ thick granite slabs that I used as socles, so I could use vertical reinforcement anchored in the concrete foundation.I will not use cliche word “butter” when describing the drilling process. It may be used for describing concrete coring, which is very easy compared to finely grained, igneous stone. Some instructions for drilling stone:1. Get a good coring bit, Zenesis technology. Chinese cheap bits will do one hole and the second will be just torture for the operator. They are just useless junk and all of them look the same.2. Attach the base of the rig using heavy duty clamps – at least three. The front part of the base should have two clamps – this is the point where the greatest force will act on the base and will try to lift it, which will cause moving the bit of the vertical line which will cause more drag. The operator will press harder and will cause even more lifting. So clamping is crucial to success.3. Use a lot of water. I was using an MK Diamond pump, but more water from a garden hose would help to remove the slurry faster.4. After drilling two, three holes in such a thick rock material, the bit will get glazed, but it will depend on the hardiness and crystalline structure of the stone. Use an ordinary 12×12″x2″ (or larger) concrete paver from home improvement store and run the bit dry, making at least 5 holes, 2 inch deep, pressing it quite hard. I have also tried a concrete block, brick and a dressing stone but the cheap paver worked the best. For me it was a crucial operation, because after drilling four holes I was unable to drill a fifth one – using a brand new quality bit.This way I was able to drill 42 holes. It took about 15 minutes per hole for just drilling. Positioning, clamping, and dressing took another 10 minutes per hole.Happy coring!