Cleveland C70284 Drill Bit Letter F 135 Point Hss

Product Description

The CLEVELAND C70284 is a screw machine length drill bit sized at Letter F (0.2570 inches) and manufactured from high-speed steel with a bright, uncoated finish. It features a 135-degree split point with web thinning, which reduces walking on entry and lowers the thrust required to start a hole. The two-flute, regular spiral design with a parallel web configuration handles a wide range of materials efficiently. At 2-5/8 inches overall length, this stub-length bit is well suited to production drilling environments where rigidity and speed matter. Licensed HVAC technicians, machinists, and maintenance trades install bits of this type daily in drill presses and hand-held power drills.

This bit is built for heavy-duty drilling applications in alloy steel and aluminum, and it performs reliably in screw machine and production drilling setups where shorter overall length reduces deflection and improves hole accuracy. The straight cylindrical shank, measuring 0.2570 inches in diameter and 1-3/16 inches in length, fits standard drill chucks without adapters. The 1-7/16-inch flute length provides adequate chip clearance for the depths typical in screw machine work. Machinists, tool-and-die trades, and general maintenance professionals reach for this style of bit when throughput and dimensional consistency are priorities.

Key Features

• Letter F size (0.2570 inches) with a diameter tolerance of +0.0000 to -0.0010 inches for tight, repeatable holes
• 135-degree split point with web thinning reduces thrust and eliminates the need for a center punch on most metals
• High-speed steel construction rated for heavy-duty service in alloy steel and aluminum
• Screw machine (stub) length of 2-5/8 inches overall increases rigidity and reduces deflection versus jobber-length bits
• Bright, uncoated finish allows easy visual inspection of the cutting edges between uses
• Meets ASME B94.11M and NAS 907 Type C specifications

Compatibility

Designed as a direct-fit replacement or production-supply bit for applications requiring a Letter F diameter hole in alloy steel or aluminum; fits any standard drill chuck accepting a 0.2570-inch straight cylindrical shank.

Installation Notes

Always secure the workpiece fully before drilling and confirm the drill chuck is tightened to the shank. Power down and de-energize any machine tool before changing bits. Use appropriate cutting fluid for the workpiece material to extend edge life and maintain hole tolerance. Inspect the split point for chipping or wear before each use; a damaged point will compromise hole size and surface finish.