Precision Twist Drill 5996982 No. 21 Hss Jobber Drill Bit

Product Description

The PRECISION TWIST DRILL 5996982 is a No. 21 wire-size jobber-length drill bit designed for general-purpose drilling in a wide range of metallic and hard materials. It measures 0.1590 inches in diameter and 3.25 inches overall, with a 2.125-inch spiral flute length. The 135-degree split-point geometry reduces walking on entry and requires less feed pressure than a standard 118-degree point. The bright, uncoated high speed steel construction is suited for shops where bit regrinding is routine. Two regular spiral flutes provide chip evacuation in typical through-hole and blind-hole drilling operations.

This drill bit fits production and maintenance drilling applications across metalworking, fabrication, and general mechanical trades. The straight cylindrical shank seats in standard drill chucks found on drill presses, hand drills, and CNC drilling setups. The QC21P series targets heavy-duty general-purpose use on steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium. Maximum drilling depth is 2.125 inches, making it appropriate for through-hole work in stock up to that depth without pecking cycles on most setups.

Key Features

• 135-degree web-thinned point reduces thrust and minimizes bit walk on hard materials
• High speed steel construction supports regrinding for extended service life
• Bright uncoated finish compatible with standard cutting fluids and oils
• Regular spiral flute with tapered web for consistent chip evacuation
• Straight cylindrical shank fits standard 3-jaw drill chucks without adapters
• ANSI-specification geometry ensures dimensional interchangeability

Compatibility

Designed for use on steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium. Fits any drill press, hand drill, or CNC drill head equipped with a chuck that accepts a 0.1590-inch straight cylindrical shank.

Installation Notes

Secure the shank fully in the chuck jaws before tightening to prevent runout. Apply a suitable cutting fluid or oil when drilling steel, stainless steel, or titanium to extend edge life and improve hole finish. Reduce spindle speed and increase feed pressure gradually when drilling hard materials or superalloys. Inspect the cutting edges before each use and regrind or replace the bit if chipping or wear is visible.