Value Collection -20870-R Letter R Hss Mechanics Drill Bit

Product Description

The VALUE COLLECTION -20870-R is a Letter R mechanics drill bit designed for general-purpose drilling in metal and ferrous materials. It measures 0.3390 inches in diameter and features a 135-degree split point that reduces walking on contact, allowing the bit to self-center without a punch mark. The oxide-coated high-speed steel body handles the heat generated during drilling in tough materials. The Weldon flat shank with three flats locks securely into compatible chuck holders, preventing slippage under torque. This bit is well-suited for use by machinists, maintenance techs, and metal fabricators working in shop or field environments.

The -20870-R is sized for Letter R applications commonly encountered when drilling clearance or tap holes in carbon steel, cast iron, high alloy steel, stainless steel, and high tensile strength alloy stock. Its mechanics-length body keeps the tool compact and stiff for close-quarters or drill-press work. The spiral flute geometry evacuates chips efficiently during through-hole and blind-hole drilling. The web-thinned, parallel web configuration reduces thrust load, making it appropriate for both hand-held and machine-mounted drilling operations.

Key Features

• Letter R diameter (0.3390 inches) for precise clearance and tap-hole sizing
• 135-degree split point self-centers and reduces drill walking
• High-speed steel construction with oxide finish for heat and wear resistance
• Weldon flat shank with 3 flats prevents rotation in compatible holders
• Web-thinned parallel web reduces drilling thrust load
• Right-hand cut spiral flute for efficient chip evacuation

Compatibility

Designed for use in drill presses, milling machines, and hand drills equipped with Weldon flat shank tool holders. Suitable for drilling carbon steel, cast iron, high alloy steel, stainless steel, high tensile strength alloy, and similar ferrous workpiece materials.

Installation Notes

Secure the Weldon shank firmly in a compatible holder, ensuring all three flats are engaged by the set screws before operation. Always power down and lock out the machine before changing bits. Use appropriate cutting fluid when drilling stainless steel or high-alloy materials to extend tool life and manage heat buildup. Inspect the cutting edges for wear or chipping before each use and replace the bit if the point is degraded.