Chicago-latrobe 47311 Jobber Drill 7.30mm Hss Black Oxide

Product Description

The CHICAGO-LATROBE 47311 is a jobber-length twist drill bit ground from high-speed steel (HSS) and finished with a black oxide coating for corrosion resistance and reduced friction at the cutting edge. It carries a 7.30 mm (0.2874 inch) diameter with a standard 118-degree split point and a web-thinned tip that reduces entry force and helps the bit self-center on the workpiece. Overall length is 109.00 mm (4.29 inches), with a 69.00 mm (2.72 inch) flute length and a straight cylindrical shank. Built to DIN 338 specification, this bit is suited for general-purpose metal drilling and belongs to the Chicago-Latrobe Series 150 line. Machinists, maintenance technicians, and metalworking trades stock it as a reliable production-floor or service-truck staple.

This bit is designed for drilling steel and cast iron in general-purpose applications. The regular spiral flute geometry provides efficient chip evacuation in moderate-depth holes typical of fabrication, repair, and maintenance work. The 40.00 mm (1.57 inch) straight shank fits standard drill chucks on bench drills, hand drills, and CNC drill presses. It is appropriate for both manual feed and light machine-feed setups where a jobber-length reach is sufficient. The DIN 338 standard governs diameter tolerance, point geometry, and overall dimensions, making this bit a drop-in match for other DIN 338 conforming tooling.

Key Features

• 7.30 mm (0.2874 inch) diameter ground to DIN 338 tolerance of -0.0010 to 0.0000 inches
• 118-degree standard point with web-thinned, tapered web for reduced thrust and easier starting
• High-speed steel construction rated for steel and cast iron workpieces
• Black oxide finish reduces friction and provides light corrosion resistance
• Regular right-hand spiral flute clears chips efficiently in through-hole and blind-hole drilling
• Straight cylindrical shank fits standard three-jaw drill chucks without adapters

Compatibility

Designed as a general-purpose jobber-length drill bit conforming to DIN 338, suitable for use in any standard drill chuck accepting a 0.2874 inch straight shank across bench drill presses, hand drills, and compatible CNC drilling equipment.

Installation Notes

Secure the shank fully in the drill chuck and verify concentricity before beginning a cut. Use cutting fluid or coolant when drilling steel or cast iron to extend tool life and maintain tolerance. Power down and lock out the machine before changing bits or clearing chip buildup from the flutes. Do not force the bit at excessive feed rates, as HSS tooling is susceptible to heat damage when overloaded without coolant.