The 2" core drill did the job, with considerable difficulty. The "body" (the red tube) had a great tendency to rub against the cored hole, as the core drill & drill gun were difficult to hold in exactly the perpendicular plains. This produced considerable chatter, making cutting progress more difficult, and greatly increasing the operator workload. Solution-reduce the "tube" diameter slightly (.062?), thus reducing the tendency for the tube to drag in the cored bore. EDiamond Tools did an excellent job with customer service with helpful, knowledgeable staff and very timely shipping. Ya done good! :)