Sumitomo U101083 Screw Machine Drill Bit 0.266 in Carbide

Product Description

The SUMITOMO U101083 is a solid carbide screw machine length drill bit designed for high-performance hole-making in ferrous materials. Built to MDW-GS series specifications, this 17/64 inch (0.2660 inch decimal) diameter bit features a 135-degree split-point geometry and a tapered web configuration that reduces thrust and improves chip evacuation. With an overall length of 2.874 inches and a flute length of 1.299 inches, it is sized for compact, rigid setups in CNC machining centers, drill presses, and automated production equipment. This tool is installed and operated by machinists, tool-and-die professionals, and industrial maintenance technicians working in production or job-shop environments.

The U101083 is suited for drilling cast iron and steel in applications where a short, stiff tool is required to maintain hole location accuracy and minimize deflection. Its screw machine length profile makes it a standard choice for turret lathes, screw machines, and short-reach CNC operations. The 2xD flute-to-diameter ratio and straight-cylindrical shank provide consistent seating in standard drill chucks and collet holders. Maximum drilling depth is 0.900 inches, appropriate for through-hole and shallow blind-hole work in production runs.

Key Features

• Solid carbide construction for rigidity and wear resistance in ferrous materials
• 135-degree split-point angle reduces walking and lowers entry thrust
• Tapered web configuration improves chip flow and reduces heat buildup
• Screw machine length (2.874 inches overall) provides maximum rigidity in tight setups
• Straight-cylindrical shank with h8 diameter tolerance for precise chuck and collet fit
• 2-flute design with 2xD flute ratio balances chip clearance and core strength

Compatibility

Designed for use in standard drill chucks and collet holders accepting a straight-cylindrical shank. Primary workpiece materials are cast iron and steel. Part of the MDW-GS series with a drill bit size range of 0.2500 to 0.3000 inches decimal.

Installation Notes

Solid carbide tooling should be installed by qualified machinists following standard tool-change lockout procedures for the machine in use. Ensure the shank is fully seated and the chuck or collet is torqued to the machine manufacturer specification before operation. Carbide is brittle — avoid side loading, interrupted cuts beyond the tool rating, or using the bit as a pry or lever. Coolant-through is not supported on this tool; apply flood or mist coolant externally if required by the application.