Osg 1302002501 Spiral Flute Tap 5/8-11 Unc 4 Flutes Hss

Product Description

The OSG 1302002501 is a spiral flute bottoming tap designed to cut internal threads in blind holes where full thread depth close to the bottom is required. Built from high-speed steel with a steam oxide coating, it cuts 5/8-11 UNC threads to a 3B class of fit with a right-hand thread direction. The 45-degree helix angle drives chips up and out of the hole, reducing clogging and improving thread quality. With an overall length of 3.813 inches and a thread length of 0.728 inches, this tap suits production and maintenance threading operations handled by machinists and tool-room professionals.

This tap is suited for threading blind holes in a range of materials including aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. It is part of the OSG Series 13020 and is appropriate for use in CNC machining centers, manual mills, and drill presses equipped with a tapping attachment. The bottoming chamfer style makes it the correct choice when threads must extend to within a few pitches of the bottom of a blind hole.

Key Features

• 5/8-11 UNC thread form, 3B class of fit, right-hand thread direction
• Bottoming chamfer for threading close to the bottom of blind holes
• 45-degree helix angle promotes upward chip evacuation in blind-hole applications
• High-speed steel construction with steam oxide coating for lubricity and corrosion resistance
• 4 spiral flutes, H3 thread limit for consistent tolerance control
• Compatible with aluminum, cast iron, and carbon steel workpieces

Compatibility

Designed for threading 5/8-11 UNC blind holes in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel workpieces per the material application data provided by OSG for Series 13020.

Installation Notes

Tap installation should be performed by a qualified machinist using a properly aligned tapping head or rigid tapping cycle to prevent tap breakage. Ensure the workpiece is securely fixtured and the tap is aligned perpendicular to the drilled hole before beginning the threading operation. Use an appropriate cutting fluid or tapping compound for the workpiece material. Always back the tap out periodically to clear chips when operating manually.