Osg 1123700 Straight Flute Tap 5/8-11 Unc Plug 3B Hss

Product Description

The OSG 1123700 is a straight flute tap designed to cut 5/8-11 UNC internal threads in a range of ferrous and non-ferrous materials. Built from high-speed steel with a bright, uncoated finish, this plug-chamfer tap provides a balance between starting ease and thread engagement depth. It carries a 3B class of fit and an H3 thread limit, making it suitable for standard tolerance through-hole and blind-hole tapping applications. With 4 flutes and a right-hand thread direction, it handles material removal efficiently in general-purpose production and maintenance environments. The overall length is 3-13/16 inches and the thread length is 1-13/16 inches.

This tap is used in machine-shop, maintenance, and production environments where 5/8-11 UNC threads are required. The plug chamfer - typically 3 to 5 lead threads - allows the tap to start cleanly in a pre-drilled hole and is the most widely used chamfer style for both through-hole and moderately deep blind-hole work. Rated material applications include aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel, covering the majority of general machining scenarios.

Key Features

• 5/8-11 UNC thread form with right-hand cutting direction
• 4 straight flutes for effective chip evacuation in short-chipping materials
• Plug chamfer for versatile through-hole and blind-hole use
• H3 thread limit and 3B class of fit for standard tolerance threading
• High-speed steel construction with bright, uncoated finish
• No coolant-through requirement - compatible with flood or manual lubrication

Compatibility

Rated for use in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. Part of OSG Series 101.

Installation Notes

This tap is installed by machinists and maintenance technicians using a tap wrench, tapping head, or CNC machine tapping cycle. Always drill the correct tap drill size for 5/8-11 UNC before tapping and ensure the workpiece is securely fixtured. Apply appropriate cutting fluid for the workpiece material to extend tap life and improve thread quality. Back the tap out periodically in manual operations to break chips and prevent binding.