Import -20870-W Letter W Mechanics Drill Bit Hss

Product Description

The IMPORT -20870-W is a Letter W mechanics drill bit designed for general-purpose metal drilling in professional and industrial settings. Built from high-speed steel (HSS) with an oxide finish, it features a 135-degree split point and web-thinned tip geometry that reduces walking on entry and lowers the thrust needed to start a hole. The Weldon flat shank with three flats locks securely in compatible chuck holders, preventing slippage under load. At 0.386 inches in diameter and 4.3125 inches overall length, this bit is a standard choice for machinists, maintenance mechanics, and fabricators working in production or repair environments.

This drill bit is suited for right-hand cutting in carbon steel, cast iron, high alloy steel, high tensile strength alloy, stainless steel, and general steel stock. The mechanics-length body keeps the bit rigid in close-quarters drilling applications on fixtures, weldments, and machine frames where a jobber-length bit would flex or chatter. The spiral flute design clears chips efficiently during through-hole and blind-hole drilling in both manual drill presses and CNC setups.

Key Features

• Letter W diameter — 0.386 inches — for standard fractional and lettered hole sizing
• 135-degree split point with web thinning reduces thrust and eliminates center-punch requirement on most metals
• High-speed steel construction handles intermittent heat buildup in production drilling
• Weldon flat shank with three flats prevents rotation in set-screw chuck holders
• Oxide coating provides light corrosion resistance and reduces friction during cutting
• Parallel web and regular spiral flute geometry optimize chip evacuation in ferrous materials

Compatibility

Designed as a general-purpose replacement or stock drill bit for use in drill presses, milling machines, and hand-held drilling equipment fitted with Weldon-compatible chuck holders or end-mill holders accepting a 3-flat shank.

Installation Notes

Installation is performed by machinists, tool-and-die workers, or maintenance mechanics. Secure the Weldon shank fully into the holder and tighten all set screws against the flats before operation. Ensure the workpiece is clamped or fixtured — never hand-hold metal stock during drilling. Coolant or cutting oil is recommended when drilling stainless steel or high alloy steel to extend tool life, as this bit does not have through-coolant capability.