01M558 - Walter SST+ 29/32-Inch Prentice Drill Bit with 1/2-Inch Shank

High-Performance Drilling with Walter SST+ Technology

The Walter 01M558 29/32" SST+ Prentice Drill is an industrial-grade cutting tool engineered for professionals who demand precision, durability, and efficiency. Part of Walter's renowned SST+ family, this drill bit is manufactured from a specialized cobalt blend high-speed steel. This metallurgical composition provides exceptional hardness and heat resistance, making it the ideal choice for drilling through tough materials such as stainless steel, which tends to work-harden during machining. The addition of cobalt ensures that the cutting edges retain their sharpness significantly longer than standard high-speed steel bits, reducing downtime for sharpening and replacement.

One of the standout features of this Prentice-style drill is its 1/2-inch reduced shank. This design allows operators to drill large-diameter holes (29/32") using standard portable power drills or drill presses that are limited to a 1/2-inch chuck capacity. To address the common issue of round shanks spinning under high torque, Walter has machined three distinct flats onto the shank. These flats provide a positive lock within the chuck jaws, ensuring maximum torque transmission and preventing the bit from slipping, which can damage both the tool and the workpiece.

The geometry of the 01M558 is designed for speed and accuracy. It features an exclusive self-centering 135° split point that bites into the metal immediately upon contact. This eliminates the phenomenon of "walking" or wandering across the surface, thereby removing the need for center punching or pre-drilling pilot holes. The bit is finished with a special bronze SST surface treatment, which acts as a lubricant to reduce friction and heat buildup while facilitating smooth chip evacuation. Whether used in a stationary magnetic drill or a handheld unit, this bit delivers clean, round holes with minimal effort.

Key Technical Benefits

• Cobalt Blend Matrix: Withstands high temperatures generated when drilling hard alloys.
• Secure Grip: Three flats on the shank prevent chuck slippage, ensuring safety and efficiency.
• Precision Point: 135° split point geometry allows for faster penetration with less feed pressure.
• Versatility: Suitable for round surfaces, heavy-gauge plate, and general fabrication tasks.