Cleveland C70258 Screw Machine Drill Bit 11/64 in Hss

Product Description

The CLEVELAND C70258 is a screw machine length drill bit designed for high-speed steel drilling in tight-clearance applications where a standard jobber-length bit is too long. At 11/64 inches (0.1719 inches) in diameter, this two-flute, right-hand-cut bit features a 135-degree split point that reduces walking at entry and lowers thrust force during penetration. The shortened screw machine length keeps the bit rigid and reduces deflection in turret lathes, CNC machining centers, and drill presses used for production work. The bright, uncoated finish means there is no coating to chip or delaminate during high-volume runs.

This bit is suited for production and maintenance drilling in alloy steel and aluminum workpieces. Its parallel web configuration with web thinning improves chip evacuation and reduces heat buildup during extended use. The straight-cylindrical shank seats cleanly in standard drill chucks and quick-change holders without the slippage risk of reduced-shank designs. Machinists, millwrights, and maintenance mechanics working on repetitive small-diameter hole requirements will find this a direct fit for screw machine operations.

Key Features

• 135-degree split point reduces drill walking and entry thrust on alloy and aluminum workpieces
• Screw machine length body at 2-1/8 inches OAL increases rigidity and reduces deflection versus jobber-length bits
• High-speed steel construction rated heavy duty for production-volume applications
• Web-thinned, parallel web design improves chip flow and limits heat accumulation
• Bright, uncoated finish — no coating delamination risk in high-cycle drilling
• Diameter tolerance held to +0.0000 to -0.0007 inches for consistent hole sizing
• Meets ASME B94.11M and NAS 907 Type C specifications

Compatibility

Designed as a direct-fit screw machine length drill bit for standard drill chucks and quick-change toolholders accepting a 0.1719-inch straight-cylindrical shank. Primary workpiece materials are alloy steel and aluminum per Series 2330 application data.

Installation Notes

A licensed machinist or qualified maintenance technician should install and operate this bit using appropriate machine guarding per shop safety standards. Secure the shank fully in the chuck before powering the machine and verify chuck runout is within acceptable limits before production drilling. Do not exceed the recommended feed and speed range for the workpiece material and bit diameter. Coolant through is not supported on this bit; apply cutting fluid externally when drilling alloy steels to manage heat.