Osg 1123402 Straight Flute Tap 9/16-18 Unf Plug Hss

Product Description

The OSG 1123402 is a straight flute plug tap designed for cutting internal right-hand threads in a range of ferrous and non-ferrous materials. Manufactured from high-speed steel, it produces 9/16-18 UNF threads and carries an H3 thread limit for consistent dimensional accuracy across production runs. The tap features 4 flutes with a plug chamfer, which provides a moderate lead-in of approximately 3 to 5 threads and suits through-hole and moderately deep blind-hole applications. With a thread length of 1-21/32 inches and an overall length of 3-19/32 inches, it fits standard tap holders and machine spindles. Machinists, tool-and-die makers, and maintenance technicians install this tap in manual and CNC tapping operations.

This tap is suited for production and maintenance tapping in materials including aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. The plug chamfer makes it a practical choice for general-purpose tapping where a starting tap is not required. It is commonly used in job shops, manufacturing facilities, and field maintenance settings where UNF thread fastener sizes are standard.

Key Features

• 9/16-18 UNF thread form for unified fine-pitch internal threads
• Plug chamfer provides moderate lead-in suitable for through-holes and open blind holes
• H3 thread limit for consistent tolerance control in production tapping
• 4 straight flutes for chip clearance in short-chipping materials
• High-speed steel construction provides durability across a broad material range
• No coolant-through requirement simplifies setup in standard tap holders

Compatibility

Compatible with aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel workpieces. Designed as an OEM-style straight flute plug tap in OSG Series 101 for standard 9/16-18 UNF tapping applications.

Installation Notes

Install this tap in a properly sized tap holder or tapping chuck rated for the spindle speed appropriate to the workpiece material. Ensure the workpiece is securely fixtured and the drill hole diameter matches the recommended tap drill size for 9/16-18 UNF before starting. Apply a suitable cutting fluid for the material being tapped; dry tapping is not recommended for steel. Follow applicable shop safety practices and power down or de-energize any machine before changing tooling.