Osg 1682300 Straight Flute Tap 15/16-20 Unef Plug Hss

Product Description

The OSG 1682300 is a straight flute plug tap designed for cutting right-hand internal threads to the 15/16-20 UNEF thread standard. Built from high-speed steel with a bright/uncoated finish, it features 6 flutes and a plug chamfer entry, making it well suited for through-hole tapping applications where chip evacuation in shorter, segmented passes is manageable. The H3 thread limit designation indicates a ground-thread tolerance class appropriate for standard fit threaded assemblies. Overall length is 4-29/32 inches with a thread length of 2-7/32 inches and a shank diameter of 0.76 inches.

This tap is intended for use in machine shop, maintenance, and production environments where fine unified thread forms are required. The 15/16-20 UNEF designation is common in precision mechanical assemblies, instrumentation, and hydraulic fittings. Material application data indicates suitability for aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. It is sized and configured for use in CNC machining centers, turret lathes, or manual tapping setups with a rigid or floating tap holder.

Key Features

• 15/16-20 UNEF right-hand thread form with H3 ground-thread tolerance
• 6-flute design supports stable cutting action in a range of ferrous and non-ferrous materials
• Plug chamfer provides gradual thread engagement - suitable for through-hole and sufficiently deep blind-hole applications
• High-speed steel construction offers toughness and resharpening capability
• Bright/uncoated finish - no coating buildup affecting thread tolerance
• Series 101N - OSG standard production tap series

Compatibility

Designed for tapping 15/16-20 UNEF threaded holes in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel workpieces. Coolant-through capability is not available on this tap.

Installation Notes

Installation and use should be performed by a qualified machinist or tooling technician familiar with tapping feeds, speeds, and cutting fluid selection for the workpiece material. Secure the tap in a rigid holder or floating tap holder sized for the 0.76-inch shank diameter before operation. Power down or disengage the spindle before loading or removing the tap. Do not force the tap against the bottom of a blind hole without accounting for the plug chamfer thread lead length.