Osg 10358005 Screw Machine Drill Bit Letter T Cobalt Tin

Product Description

The OSG 10358005 is a screw machine length drill bit designed for high-performance drilling in steel and other ferrous materials. It is ground from cobalt high speed steel and finished with a titanium nitride (TiN) coating that extends cutting life and reduces heat buildup at the cutting edge. The drill features a 130-degree split point for reduced thrust and self-centering entry, along with a right-hand, regular spiral flute geometry and an R-thinned web for improved chip evacuation. Overall length is 3-9/16 inches with a flute length of 1-3/4 inches, and the straight shank measures 0.3750 inches in diameter. This bit is used by machinists, toolroom technicians, and maintenance trades working on production or repair applications.

The 10358005 is sized at letter T, equivalent to 0.3580 decimal inches or 9.09 mm, placing it in the 0.3500 to 0.4000 decimal inch diameter range. The screw machine length format — shorter than jobber length — is suited for drill press, CNC, and turret lathe work where rigidity and minimal deflection matter. This bit is particularly effective in steel and hard ferrous alloys where cobalt-grade tooling is specified over standard high speed steel. The TiN coating adds surface hardness and lubricity, allowing higher feed rates before tool wear becomes critical. Two flutes and a tapered web configuration help clear chips efficiently in short-hole applications.

Key Features

• Cobalt high speed steel construction for elevated heat resistance in ferrous drilling
• TiN coating increases surface hardness and extends cutting tool life
• 130-degree standard point angle with R-thinned web reduces entry thrust and centers the bit without a pilot
• Screw machine length body provides added rigidity over jobber length bits
• Straight cylindrical shank at 0.3750 inches fits standard drill chucks and collet holders
• Right-hand, regular spiral flute with tapered web promotes consistent chip evacuation
• Drill bit diameter tolerance held to plus 0 to minus 0.022 mm for close-tolerance hole applications

Compatibility

Designed as an OEM-style screw machine length drill bit for use in drill presses, CNC machining centers, turret lathes, and similar machine tool setups that accept a straight cylindrical shank. Primary workpiece material is steel.

Installation Notes

This drill bit is installed by machinists or toolroom technicians into a drill chuck or collet holder rated for the 0.3750-inch straight shank diameter. Ensure the machine spindle is fully stopped and locked out before changing tooling. Verify chuck or collet runout is within acceptable limits before drilling to avoid premature edge wear. Follow applicable shop safety practices and machine manufacturer guidelines for speed and feed selection when working with cobalt tooling in steel.