Sumitomo 5UHY046 Screw Machine Drill Bit 0.2559 in

Product Description

The SUMITOMO 5UHY046 is a screw machine length drill bit engineered for high-performance drilling in cast iron and steel. Built from solid carbide with a coated finish, it delivers the hardness and wear resistance needed for production drilling environments. The bit measures 6.50 mm (0.2559 inches) in diameter with a 135-degree split-point geometry that reduces thrust and improves self-centering on entry. At 73 mm (2.874 inches) overall length, this is a stub-style bit suited to close-clearance and short-travel drilling applications. It features a straight-cylindrical shank and is part of the MDW-GS series. Licensed machinists, toolroom technicians, and CNC setup personnel are the typical users.

This drill bit is designed for screw machine and short-hole drilling operations in ferrous materials, specifically cast iron and steel. The 2xD flute-to-diameter ratio and tapered web configuration promote chip evacuation and reduce walking on hard materials. It fits standard drill chucks and collet holders accepting a 7 mm straight shank. Typical applications include production machining, component drilling on CNC machining centers, and manual drill press work where short flute length aids rigidity and accuracy.

Key Features

• Solid carbide construction for hardness and wear resistance in ferrous materials
• 135-degree drill point angle for reduced entry thrust and improved self-centering
• Coated finish extends tool life in cast iron and steel applications
• Tapered web configuration supports chip flow and reduces cutting resistance
• Straight-cylindrical shank fits standard chucks and collet holders accepting 7 mm shanks
• Screw machine length (stub) design maximizes rigidity in short-travel drilling setups

Compatibility

Designed as a direct-fit replacement within the SUMITOMO MDW-GS series for drilling cast iron and steel workpieces; compatible with drill chucks and collet systems accepting a 7 mm straight-cylindrical shank.

Installation Notes

Install in a properly sized collet or drill chuck rated for the shank diameter before use. Ensure the machine spindle is fully stopped and locked out before changing tooling. Solid carbide bits are brittle compared to HSS — avoid side-loading or interrupted cuts that could cause chipping. Verify runout with a dial indicator after seating to protect both the tool and the workpiece.