Boring achieves three things: Sizing: Boring brings the hole to the proper size and finish. A drill or reamer can only be used if ... At the same time, the machine, boring bar and tool clamping must ...

No workshop is complete without a good cordless drill ... We bore a 1/2-inch hole through a 2x4 with a standard bit in about half a second and a one-inch hole with a paddle bit in three seconds ...

Three days later ... Workers finally powered up the tunnel-boring machine on Dec. 22, 2015 after a two-year delay. Less than a month later, the drill broke through the concrete, repair ...