01M556 - Walter SST+ 7/8-Inch Cobalt Prentice Drill Bit

Heavy-Duty Precision with Walter SST+ Prentice Drills

The Walter 01M556 SST+ 7/8" Prentice Drill is a high-performance cutting tool engineered for maintenance, repair, and operations (MRO) professionals who demand reliability and speed. Part of the renowned SST+ family, this drill bit is specifically designed to bridge the gap between large-diameter hole requirements and standard portable drilling equipment. With a 7/8-inch cutting diameter reduced to a 1/2-inch shank, it allows operators to utilize standard 1/2-inch capacity chucks on portable drills, drill presses, and magnetic base units to bore significant holes without needing specialized heavy machinery.

What sets the 01M556 apart is its advanced metallurgy and geometry. Constructed from a premium cobalt blend, this bit withstands the high temperatures generated when drilling tough alloys like stainless steel and structural steel. The addition of cobalt significantly extends the cutting edge's life, reducing the frequency of resharpening and lowering overall tooling costs. The bit features Walter's exclusive self-centering point geometry, which bites into the material immediately upon contact. This eliminates the time-consuming step of center punching or drilling pilot holes, streamlining the fabrication process.

Slippage is a common failure point in large-diameter drilling with round shanks. Walter addresses this with a precision-machined shank featuring three flats. This "Prentice" style design ensures a positive lock within the chuck jaws, transmitting maximum torque to the cutting edge without the bit spinning inside the tool. Finished with a special bronze SST surface treatment, the bit evacuates chips efficiently and reduces friction, ensuring smooth, accurate holes every time.