Sumitomo U101034 Screw Machine Drill Bit 0.1695in Carbide

Product Description

The SUMITOMO U101034 is a screw machine length drill bit designed for precision drilling in cast iron and steel. Built from solid carbide with a coated finish, it delivers the hardness and wear resistance required for ferrous materials in production and maintenance machining environments. The 135-degree split-point tip reduces walking and lowers the thrust needed to start the hole without a center punch. At 0.1695 inches (4.31 mm) in diameter, this bit is suited for close-tolerance work, with a diameter tolerance of h8. Overall length is 2.4016 inches, keeping it rigid and minimizing deflection in short-reach applications. Machinists and toolroom technicians working in CNC or manual drill press setups will find it a reliable production-grade option.

The U101034 belongs to SUMITOMO's MDW-GS series and is intended for screw machine length drilling operations where stub rigidity matters. Primary workpiece materials are cast iron and steel, making it a fit for automotive, fabrication, and general metalworking applications. The straight-cylindrical shank seats cleanly in standard chucks and collets. With a flute-to-diameter ratio of 2xD and a maximum drilling depth of 0.6510 inches (16.54 mm), it is optimized for shallow, high-volume hole production rather than deep-hole boring.

Key Features

• Solid carbide construction for hardness and thermal resistance in ferrous materials
• 135-degree drill point angle reduces walking and entry thrust
• Coated finish extends tool life in abrasive cast iron and steel applications
• Tapered web configuration improves chip evacuation in the 2-flute geometry
• h8 diameter tolerance supports close-tolerance hole sizing
• Straight-cylindrical shank fits standard drill chucks and collets without adapters

Compatibility

Designed for use in CNC machining centers, screw machines, and manual drill presses where a straight-cylindrical shank is accepted. Rated for primary workpiece materials of cast iron and steel. Part of the SUMITOMO MDW-GS series.

Installation Notes

Installation and use should be performed by qualified machinists or toolroom technicians familiar with carbide tooling. Solid carbide bits are brittle compared to HSS; avoid side loading, interrupted cuts without proper feed-rate adjustment, or dropping the bit on hard surfaces. Secure the shank fully in the chuck or collet before operation and verify spindle runout is within acceptable limits to protect the h8 tolerance edge. Follow machine manufacturer guidelines and applicable shop safety standards for speeds and feeds when drilling ferrous materials.