Walter SST+ 39/64-Inch Prentice Drill Bit with 1/2-Inch Shank

The Ultimate Drill Bit for Stainless Steel Fabrication

For welders and fabricators, drilling large holes in stainless steel on the job site can be a frustrating challenge. The Walter 01M539 39/64" SST+ Prentice Drill Bit is the solution designed specifically for your needs. When you need to drill a hole larger than half an inch but only have a standard 1/2-inch chuck drill available, this reduced-shank bit gets the job done. It is perfectly sized for creating clearance holes for bolts or fluid pass-throughs in heavy metal fabrication projects.

What sets the Walter SST+ apart is its ability to handle the heat. Stainless steel work hardens quickly if a drill bit drags or dulls, but this bit is crafted from a high-performance cobalt blend that maintains hardness at high temperatures. The bronze SST surface treatment further aids in cutting by reducing friction, ensuring that the bit cuts freely rather than rubbing. This means you get more holes per bit and spend less time sharpening or replacing tools. It is tough enough for heavy-duty structural steel yet precise enough for non-ferrous applications.

One of the biggest annoyances with large diameter drill bits is shank slippage. When a round shank spins inside the chuck, it damages both the bit and the drill. Walter has solved this with a secure 3-flat shank design. This ensures your drill's chuck jaws get a solid grip, transmitting all the torque directly to the cutting edge. Additionally, the advanced point geometry allows you to start drilling exactly where you marked, without a center punch or pilot bit. For reliable, heavy-duty drilling in the shop or out in the field, trust Walter SST+ technology.