Triumph Twist Drill 060428 Screw Machine Drill Bit 7/16 in

Product Description

The TRIUMPH TWIST DRILL 060428 is a screw machine length drill bit designed for high-production drilling in metal, steel, and other hard materials. The shortened overall length of 3-7/16 inches provides added rigidity compared to jobber-length bits, reducing deflection and improving hole accuracy in close-tolerance applications. Manufactured from high-speed steel with an oxide coating, this bit handles the heat and friction generated during continuous-duty drilling. The 135-degree split point starts on contact without center-punching and reduces thrust. A tapered web configuration further reinforces the cutting edge for heavy-duty work.

This bit is suited for use in drill presses, CNC machining centers, and manual machine tools where a stubby, rigid bit is preferred over jobber length. Typical applications include production shops, manufacturing environments, and trade professionals drilling through ferrous metals, stainless steel, cast iron, and similar materials. The straight-cylindrical shank fits standard drill chucks without adapters. This is a Series T4HD heavy-duty bit, appropriate for machinists, millwrights, and tool-and-die tradespeople who require consistent, repeatable hole geometry.

Key Features

• 135-degree split point starts on contact, eliminating the need for a center punch and reducing walking
• Screw machine (stub) length at 3-7/16 inches overall for increased rigidity and reduced deflection
• High-speed steel construction with oxide coating for heat resistance and extended tool life
• Web-thinned, tapered web configuration reduces cutting thrust and improves chip evacuation
• Right-hand spiral flute with 2-1/16 inch flute length for efficient chip clearing
• Straight-cylindrical shank fits standard three-jaw drill chucks without a sleeve or adapter

Compatibility

Designed as an OEM-style replacement or standard tooling selection for production drilling setups requiring a 7/16 inch diameter screw machine length bit with a straight-cylindrical shank.

Installation Notes

Installation is performed by machinists or qualified trade professionals. Secure the shank firmly in a properly sized drill chuck and verify runout before drilling. Always power down and de-energize the machine spindle before changing or inspecting tooling. Follow applicable shop safety practices and machine manufacturer guidelines when selecting speeds and feeds for the workpiece material.