Osg 1111000 Straight Flute Tap 5/16-24 Unf Plug Hss

Product Description

The OSG 1111000 is a straight flute plug tap designed for cutting right-hand internal threads to the 5/16-24 UNF standard. Manufactured from high-speed steel (HSS) with a bright, uncoated finish, it features 4 flutes and a plug chamfer that provides a gradual thread lead-in suited for through-hole and blind-hole applications where some lead room is available. The H2 thread limit designation indicates a tight tolerance class appropriate for standard UNF fits. With an overall length of 2-23/32 inches and a thread length of 1-1/8 inches, this tap is sized for general-purpose threading work across a wide range of materials.

This tap is intended for use in tapping operations on aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. It is suited to both manual hand-tapping and machine tapping setups where a straight flute geometry is appropriate. The plug chamfer style makes it a common choice for production and maintenance environments where through-holes or blind holes with adequate chip clearance are the norm. Machinists, maintenance technicians, and trade professionals working in HVAC, plumbing, and electrical fabrication will find this tap applicable to a broad range of threading tasks in ferrous and non-ferrous metals.

Key Features

• 5/16-24 UNF right-hand thread form for standard unified fine-thread applications
• Plug chamfer provides 3 to 5 thread lead-in for versatile through-hole and blind-hole use
• 4-flute straight flute design for rigid, guided cutting in a wide range of metals
• H2 thread limit for consistent, close-tolerance UNF fit
• High-speed steel construction for durability in ferrous and non-ferrous materials
• Bright uncoated finish - no coating variables to account for in lubrication or speed selection

Compatibility

Rated for use in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel workpieces. Designed as a standard replacement or production tap for any application requiring a 5/16-24 UNF right-hand internal thread.

Installation Notes

This tap is installed by machinists or maintenance technicians using a tap wrench for hand-tapping or a suitable tapping head for machine use. Always ensure the workpiece is securely fixtured and a correctly sized pilot hole is drilled before tapping. Apply an appropriate cutting fluid for the workpiece material to extend tool life and improve thread quality. Inspect the tap for wear or chipping before each use and replace if cutting edges are degraded.