There are three tool options to consider when drilling large-diameter holes in thick steel: twist drill bits, hole saws and annular cutters. 1. Twist drill bits. Especially in steel thicker than ¼", ...
A power drill could be called one of the patron tools of the hardware pantheon. With a simple spinning motor, a power drill can handle all kinds of different jobs, boring holes into different ...
When I was drilling through a hardened steel I went to a specialty metals shop and they recommended cobalt bits. They were also much cheaper than lows but unfortunately have since gone out of business ...