Osg 1723001 Spiral Flute Tap 3/8-16 Unc Modified Bottoming

Product Description

The OSG 1723001 is a spiral flute tap designed to cut 3/8-16 UNC right-hand internal threads in ferrous materials. Built from vanadium high-speed steel and finished with a steam oxide coating, it is engineered for threading stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel. The modified bottoming chamfer allows threading close to the bottom of a blind hole while the 45-degree helix angle evacuates chips upward, reducing clogging and tap breakage. Rated to a 2B class of fit with an H5 thread limit, it delivers consistent tolerance control. Licensed machinists, toolroom operators, and maintenance mechanics are the primary users of this tap.

The OSG 1723001 is suited to general machining, maintenance and repair operations, and production tapping where 3/8-16 UNC threads are required in blind or through holes. Its modified bottoming chamfer makes it particularly effective in blind-hole applications where a standard taper or plug tap cannot reach full thread depth. The 45-degree spiral flute geometry promotes reliable chip flow in interrupted cuts and tough alloy steels. It belongs to OSG Series 303 and is sold individually.

Key Features

• 45-degree right-hand spiral flute for upward chip evacuation in blind holes
• Modified bottoming chamfer for threading close to the bottom of a blind hole
• Vanadium high-speed steel construction for wear resistance in carbon and stainless steels
• Steam oxide coating reduces friction and provides mild corrosion protection
• H5 thread limit and 2B class of fit for standard tolerance internal threads
• No coolant-through design - suitable for conventional flood or manual lubrication

Compatibility

Designed for cutting 3/8-16 UNC 2B class internal threads in stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel workpieces. Compatible with standard 3/8-inch tap holders, T-handle wrenches, and CNC tapping chucks sized for a 0.381-inch shank diameter.

Installation Notes

This tap is installed by a machinist or toolroom technician using a tap wrench, tapping head, or rigid CNC tapping holder. The workpiece should be secured in a vise or fixture and the pilot hole drilled to the correct tap drill size for 3/8-16 UNC before tapping begins. Use a suitable cutting fluid or tapping oil for the workpiece material, especially when threading stainless steel, to reduce heat buildup and extend tool life. Back the tap out periodically to break and clear chips when working in blind holes.