Sumitomo U101141 Screw Machine Drill Bit 0.368in Carbide

Product Description

The SUMITOMO U101141 is a screw machine length drill bit designed for precision hole-making in ferrous and hard materials. Built from solid carbide with a coated finish, this bit handles cast iron and steel with consistent accuracy. The 135-degree split point reduces walking and lowers thrust at entry, making it well-suited for production drilling environments. At 0.368 inches in diameter, it corresponds to Letter Size U and carries an h8 diameter tolerance for tight fitment requirements. The straight-cylindrical shank seats cleanly in standard drill chucks and collets. This is a two-flute configuration with a tapered web and a flute-to-diameter ratio of 2xD, part of the MDW-GS series.

The U101141 is used in machining and fabrication shops where controlled, repeatable drilling into cast iron and steel is required. Screw machine length bits are shorter than jobber-length bits, which improves rigidity and reduces deflection in close-tolerance work. The bit fits manual drill presses, CNC machining centers, and screw machine setups. A maximum drilling depth of 0.9439 inches makes it appropriate for through-holes and shallow blind holes in production runs. No coolant-through capability is present, so external or flood coolant should be applied where heat management is needed.

Key Features

• Solid carbide construction provides hardness and wear resistance in steel and cast iron applications
• 135-degree drill point angle reduces entry thrust and minimizes bit walking on flat surfaces
• Coated finish extends tool life and reduces friction during cutting
• Straight-cylindrical shank fits standard chucks and collets without modification
• Tapered web design improves chip clearance and cutting efficiency
• h8 diameter tolerance supports precise hole sizing in tight-spec applications

Compatibility

Designed as a screw machine length replacement drill bit for use in cast iron and steel drilling applications. Compatible with standard drill chucks, collets, and CNC toolholders accepting straight-cylindrical shanks in the 0.35 to 0.40 inch diameter range, per the MDW-GS series specifications.

Installation Notes

Installation and use should be performed by qualified machinists or tooling technicians familiar with carbide cutting tools. Ensure the spindle and workpiece are fully secured before engaging the bit, as carbide is brittle and sensitive to lateral shock loads. No coolant-through capability is present on this bit, so external coolant or cutting fluid should be applied to manage heat during operation. Inspect the cutting edges before each use, as chipped or damaged carbide should never be run in a machine.