Osg 15358005 Cobalt Drill Bit Letter T 0.3580 in Tin

Product Description

The OSG 15358005 is a cobalt jobber length drill bit sized to Letter T (0.3580 inches / 9.09 mm), designed for high-performance drilling in steel and alloy steel. Finished with a Titanium Nitride (TiN) coating, the bit delivers extended tool life and reduced heat buildup under demanding cutting conditions. The 130-degree split point promotes self-centering and reduces walking on entry, while the R-thinned web lowers thrust requirements. With an overall length of 5-5/16 inches and a 3-1/2-inch flute length, it fits standard jobber-length applications in machine shops, fabrication, and mechanical assembly. This bit is part of OSG Series 1500 and is intended for use by machinists, millwrights, and tool-and-die professionals.

The OSG 15358005 is suited for drilling blind holes, cross holes, and through-holes in ferrous workpieces including carbon steel and alloy steel. Its straight-cylindrical 3/8-inch shank fits conventional drill chucks and collet systems on drill presses, CNC machining centers, and handheld power tools. The regular spiral flute type ensures reliable chip evacuation during standard drilling cycles. This bit is sold individually and is appropriate for both production environments and maintenance repair operations where consistent hole quality in metal is required.

Key Features

• Letter T size (0.3580 inches / 9.09 mm) with diameter tolerance of +0 to -0.022 mm
• Cobalt construction with Titanium Nitride (TiN) coating for extended wear resistance in steel
• 130-degree drill point angle with R-thinned, tapered web for self-centering entry
• Right-hand cut, 2-flute regular spiral design for consistent chip removal
• Straight-cylindrical 3/8-inch shank compatible with standard chucks and collets
• Supports blind hole, cross hole, through-hole, and self-centering drilling applications

Compatibility

Designed as an OEM-style jobber length drill bit for use in standard drill chucks, collet holders, and CNC tool holders accepting a 3/8-inch straight-cylindrical shank. Primary workpiece materials are steel and alloy steel (ISO material code P).

Installation Notes

This bit is installed by machinists or maintenance technicians into compatible drill chucks or collet systems. Ensure the machine spindle is fully stopped and the chuck is de-energized before securing or removing the bit. Use appropriate cutting fluid or coolant when drilling steel to manage heat, as coolant-through is not supported by this bit geometry. Follow applicable shop safety standards and machine manufacturer guidelines for speed and feed selection.