Cleveland C70263 Drill Bit Letter E 0.25 in 135 Point Hss

Product Description

The CLEVELAND C70263 is a screw machine length drill bit sized at Letter E (0.25 inches) and built from high-speed steel (HSS) with a bright, uncoated finish. The 135-degree split point reduces walking on entry and lowers thrust requirements, making it well suited for production drilling where cycle time and hole quality matter. The web-thinned, parallel-web construction keeps the cutting geometry consistent through the life of the bit. At 2.5 inches overall length, this stub-length format provides added rigidity compared to jobber-length bits, reducing deflection in short-reach applications. The straight-cylindrical shank measures 0.25 inches in diameter with a 1.125-inch shank length, and the drill bit diameter is held to a tolerance of plus 0.0000 to minus 0.0007 inches. Machined to ASME B94.11M standards and designated to NAS 907 Type C, this bit is appropriate for professional metalworking and machining environments.

The C70263 is designed for drilling into alloy steel and aluminum in screw machine, turret lathe, and CNC drilling operations where a short, stiff bit is required to maintain positional accuracy. The 1.375-inch flute length provides adequate chip clearance for the shallow-depth cuts typical in screw machine work. Right-hand cut, two-flute spiral configuration handles both ferrous and non-ferrous workpiece materials. This bit is sold individually but carries a minimum order quantity of 12 units, making it practical for shop stocking or toolroom inventory replenishment.

Key Features

• 135-degree split point reduces drill walk and lowers feed force on entry
• Web-thinned parallel web maintains cutting efficiency and reduces heat buildup
• Screw machine (stub) length at 2.5 inches overall provides superior rigidity over jobber-length alternatives
• High-speed steel construction with bright uncoated finish suitable for alloy steel and aluminum
• Diameter tolerance held to plus 0.0000 to minus 0.0007 inches for consistent hole sizing
• Meets ASME B94.11M and NAS 907 Type C specifications

Compatibility

Designed as an OEM-style replacement or standard toolroom stock drill bit for screw machine, turret lathe, and CNC drilling setups requiring a Letter E (0.25-inch) straight-shank stub-length bit. Primary workpiece materials listed by the manufacturer are alloy steel and aluminum.

Installation Notes

This bit is installed by machinists and tool-and-die professionals in drill chucks, collets, or turret toolholders accepting a 0.25-inch straight-cylindrical shank. Ensure the machine spindle and workpiece are secured before operation, and confirm chuck runout is within acceptable limits to preserve the stated diameter tolerance. Coolant-through is not supported on this bit; apply external cutting fluid as appropriate for the workpiece material. Follow applicable shop safety procedures and machine guarding requirements during setup and operation.