Hertel K008986AS Tap Set 3/8-16 Unc 4 Flute Hss

Product Description

The HERTEL K008986AS is a 3-piece tap set designed for cutting 3/8-16 UNC internal threads in metal workpieces. Built from high speed steel with a bright finish, this set delivers consistent thread quality across a range of ferrous and non-ferrous materials. The 4-flute geometry promotes chip evacuation and helps maintain thread accuracy during hand or machine tapping. At 2-15/16 inches overall length, the taps are sized for general-purpose threading tasks in shop, maintenance, and field environments. The set covers Class of Fit 2B and 3B, making it suitable for standard commercial threads as well as closer-tolerance applications.

This tap set is used by machinists, millwrights, maintenance technicians, and tool-and-die professionals for threading operations on steel, aluminum, cast iron, and similar materials. It is appropriate for both production shop use and on-site repair work where 3/8-16 UNC threaded holes are required. The 3-piece configuration typically includes a taper, plug, and bottoming tap, providing the range needed to start, continue, and finish a blind or through hole.

Key Features

• 3/8-16 UNC thread form for standard fastener compatibility
• 4-flute design supports chip clearance and thread accuracy
• High speed steel construction for durability across common metals
• Bright finish — no coating to add dimensional variation
• Thread Limit H5 for consistent fit within 2B and 3B Class of Fit tolerances
• 3-piece set covers taper, plug, and bottoming tap stages

Compatibility

Designed for cutting 3/8-16 UNC threads per standard UNC thread form specifications, compatible with any workpiece material and setup where H5 thread limit and 2B or 3B Class of Fit are required.

Installation Notes

Tap installation should be performed by a qualified machinist or maintenance technician familiar with threading operations. Secure the workpiece firmly before tapping and use the appropriate tap drill size for 3/8-16 UNC to achieve the correct minor diameter before engaging the tap. Apply cutting fluid rated for the workpiece material to reduce heat and extend tap life. Begin with the taper tap to start the thread, follow with the plug tap, and use the bottoming tap only when threading to the bottom of a blind hole.