M.a. Ford 20531250 Screw Machine Drill Bit 5/16 in Carbide

Product Description

The M.A. FORD 20531250 is a screw machine length drill bit engineered for high-precision drilling in demanding production and maintenance environments. Built from solid carbide, this bit delivers the rigidity and wear resistance required when working through cast iron, stainless steel, non-ferrous metals, and steel. The 135-degree split point geometry reduces walking and thrust force at entry, while the web-thinned, parallel web configuration improves chip evacuation and cutting efficiency. At 5/16 inch (0.3125 inches) in diameter, the bit maintains a tight diameter tolerance of +0.0000 to -0.0005 inches, making it suitable for applications where hole quality is critical. Licensed HVAC, plumbing, and industrial service technicians, as well as machinists and production drilling operations, are the typical installers of this tool.

This bit is designed for screw machine length applications where a compact, rigid tool is preferred over jobber or long-series alternatives. The shortened overall length of 2-13/16 inches reduces deflection and promotes straighter holes in CNC machining centers, drill presses, and hand-held drilling equipment. The 3xD flute-to-diameter ratio and slow spiral flute type are particularly well suited for chip control in materials like cast iron and stainless steel, where chip packing is a common concern. The bright, uncoated finish is appropriate for use with cutting fluids in general-purpose metal removal operations.

Key Features

• Solid carbide construction provides superior hardness and wear resistance compared to high-speed steel
• 135-degree split point reduces entry walking and lowers required feed force
• Web-thinned parallel web improves chip flow and reduces heat buildup at the cutting edge
• Screw machine length (2-13/16 inches overall) minimizes deflection in tight-clearance or high-feed setups
• Right-hand cut with slow spiral flute — optimized for cast iron, stainless steel, non-ferrous metal, and steel
• Tight diameter tolerance of +0.0000 to -0.0005 inches supports consistent, repeatable hole sizing

Compatibility

Rated for primary workpiece materials including cast iron, non-ferrous metal, stainless steel, and steel. Suitable for use in CNC machining centers, turret lathes, drill presses, and other fixed or hand-held drilling equipment accepting a 0.3125-inch straight-cylindrical shank. Part of the M.A. FORD Series 205 screw machine length carbide drill line.

Installation Notes

Install in a collet, drill chuck, or tool holder rated for the 0.3125-inch straight shank diameter and tighten securely before operation. Ensure the spindle and workpiece are properly fixtured to prevent movement during drilling. Use an appropriate cutting fluid or coolant when drilling stainless steel or ferrous materials to extend tool life and maintain surface finish. Inspect the cutting edges for wear or chipping before each use, as carbide tools are brittle and can fracture if run in damaged condition or with excessive runout.