Sumitomo U101099 Screw Machine Drill Bit 0.29in Carbide

Product Description

The SUMITOMO U101099 is a solid carbide screw machine length drill bit designed for high-performance drilling in ferrous materials. With a 0.29 inch (7.37 mm) diameter and a 135-degree split-point angle, it provides fast, accurate hole entry with minimal walking. The straight-cylindrical shank seats securely in standard drill chucks and collet holders. The coated finish improves wear resistance and extends tool life in demanding production environments. A tapered web design adds rigidity while maintaining chip clearance. This bit is suited for machinists, toolroom technicians, and production floor operators running CNC or manual drilling operations.

The U101099 is built for drilling cast iron and steel in screw machine and short-hole drilling applications. The screw machine length format — shorter than jobber length — increases rigidity and reduces deflection, making it a practical choice for high-volume or precision repetitive drilling. The 2xD flute-by-diameter ratio and 1.30 inch flute length support efficient chip evacuation at moderate drilling depths up to 0.86 inches. This bit fits into standard setups without special toolholders, making it a straightforward replacement or addition to existing drill bit inventories in machine shops and fabrication facilities.

Key Features

• Solid carbide construction for rigidity and long tool life in ferrous materials
• 135-degree drill point angle for fast cutting entry and reduced thrust force
• Coated finish increases wear resistance and reduces friction during cutting
• Tapered web configuration improves core strength and chip flow
• Straight-cylindrical shank fits standard drill chucks and collet holders
• Screw machine length format reduces deflection in repetitive drilling setups

Compatibility

Designed for use in cast iron and steel workpieces. Falls within the MDW-GS series drill bit size range of 0.25 inches to 0.30 inches (6.50 mm to 8.00 mm). Fits standard straight-shank drill chucks and collet holders accepting the h8 diameter tolerance.

Installation Notes

Installation and tool changes should be performed by a qualified machinist with the machine fully powered down and the spindle at a complete stop. Secure the shank fully within the collet or chuck to the recommended grip depth before tightening. Verify spindle speed and feed rate are appropriate for the workpiece material and bit diameter before starting the cut. Do not use coolant-through circuits with this bit as it does not support internal coolant delivery.