Chicago-latrobe 44428 Left Hand Drill Bit 7/16 Inch Hss

Product Description

The CHICAGO-LATROBE 44428 is a left-hand cut, jobber-length drill bit designed for precision drilling in ferrous metals and cast iron. Built from high-speed steel (HSS) with a bright, uncoated finish, this bit is part of the Series 150L line. It measures 7/16 inch (0.4375 inch decimal) in diameter with a 5-1/2 inch overall length and a 4-1/16 inch flute length. The 118-degree standard point angle and web-thinned, tapered web design reduce entry resistance and promote clean, accurate hole starts. A straight-cylindrical shank ensures secure chuck engagement across standard drill press and hand-drill setups. Licensed machinists, pipefitters, and metalworking tradespeople reaching for a left-hand bit will find this a reliable general-purpose option.

The 44428 is rated for use in cast iron and steel, making it well-suited to production and maintenance drilling tasks in industrial, mechanical, and plumbing trade environments. Left-hand cutting direction makes this bit particularly useful for extracting broken right-hand fasteners and studs — the bit naturally backs out a fastener as it drills into it. The regular spiral and two-flute configuration support efficient chip evacuation in through-hole and blind-hole drilling applications. This is a single-piece package, appropriate for both bench stock and individual task use.

Key Features

• Left-hand cutting direction aids in broken fastener and stud extraction
• High-speed steel construction provides durability across cast iron and steel workpieces
• Web-thinned, tapered web reduces thrust and improves hole entry
• 118-degree standard point angle suits general-purpose drilling tasks
• Straight-cylindrical shank fits standard three-jaw chucks without modification
• Bright, uncoated finish allows visual wear monitoring during service life

Compatibility

Designed as a general-purpose left-hand jobber-length drill bit compatible with any standard drill press, reversible hand drill, or screw extractor setup accepting a 7/16 inch straight-cylindrical shank. Primary workpiece materials are cast iron and steel.

Installation Notes

This bit is installed and operated by machinists, pipefitters, maintenance technicians, and general tradespeople using standard drilling equipment. Secure the shank fully in the chuck and verify the drill is set to reverse rotation before use, as this is a left-hand-cut bit. Eye protection and appropriate workholding are required; secure the workpiece firmly to prevent rotation under cutting load. Inspect the cutting edges before each use and replace the bit if chipping or excessive wear is present.