Osg 1161300 Straight Flute Tap 3/8-16 Unc Plug Hss

Product Description

The OSG 1161300 is a straight flute plug tap designed for cutting internal threads in a wide range of ferrous and non-ferrous materials. Built from high-speed steel with a bright, uncoated finish, it produces 3/8-16 UNC right-hand threads using 3 straight flutes. The plug chamfer - typically 3 to 5 threads - provides a balance between starting ease and thread engagement depth, making this tap suitable for through-hole applications. The H1 thread limit ensures close tolerance fits appropriate for standard fastener assemblies. With an overall length of 2-15/16 inches and a thread length of 1-1/4 inches, it fits standard tap wrench and machine tool setups used in job shop and maintenance environments.

This tap is suited for tapping 3/8-16 UNC threads in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. It is a common choice for general machining, maintenance and repair operations, and production tapping where a straight-flute design is appropriate for short-chipping or chip-neutral materials. The straight flute geometry works best in materials that produce broken or powdery chips rather than long stringy chips.

Key Features

• 3/8-16 UNC thread form with right-hand thread direction
• Plug chamfer for balanced starting and thread engagement in through-hole applications
• High-speed steel construction for durability across a broad range of workpiece materials
• H1 thread limit for controlled tolerance fits in standard fastener assemblies
• 3 straight flutes optimized for short-chipping materials including cast iron and aluminum
• No coolant-through requirement - compatible with standard hand or machine tapping setups

Compatibility

Designed as a standard straight flute tap compatible with tap wrenches, tapping heads, and CNC or manual machine tool holders that accept straight-shank taps in the 3/8-16 UNC size range. Material applications include aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel as specified by the manufacturer.

Installation Notes

This tap is installed by a machinist or maintenance technician using a tap wrench, tapping attachment, or machine tool spindle. Secure the workpiece fully before tapping and ensure the tap is started square to the hole to prevent thread distortion or tap breakage. Apply appropriate cutting fluid for the workpiece material - even with bright uncoated tooling, lubrication extends tool life. Follow standard shop practice and applicable safety guidelines when operating machine tools or manual tapping equipment.