Guhring 9039010254000 Spiral Point Tap 1-8 Unc

Product Description

The GUHRING 9039010254000 is a spiral point tap designed for through-hole threading in steel and similar materials. It cuts a 1-8 UNC right-hand thread using a plug chamfer entry, which distributes cutting load across several leading threads for controlled engagement. Built from HSS-E cobalt high-speed steel, it handles the elevated heat and hardness demands of steel tapping without a coating — the bright, uncoated finish suits applications where coating adhesion or contamination is a concern. With 4 flutes and an H6/H7 thread limit, this tap produces consistent Class 2B fit threads. It is part of GUHRING Series 3901 and is sized for production and maintenance use by machinists and tool-and-die professionals.

This tap is suited for through-hole threading operations in steel workpieces across production machining, maintenance repair, and fabrication environments. The 1-8 UNC thread form is a coarse-pitch designation common in structural fastener applications, fixtures, and general mechanical assemblies. The plug chamfer profile makes it appropriate for use in CNC tapping centers, drill presses, or hand tapping where a gradual thread lead-in is needed. No coolant-through feature is present, so external cutting fluid application is recommended when tapping steel.

Key Features

• 1-8 UNC coarse-pitch thread form for common structural and mechanical fastener applications
• HSS-E cobalt material provides elevated heat resistance and wear life when tapping steel
• Plug chamfer distributes cutting load gradually for controlled thread engagement
• 4 flutes deliver chip clearance and stability in through-hole operations
• H6/H7 thread limit produces Class 2B fit threads within standard tolerance
• Bright, uncoated finish — no coating interaction with workpiece or cutting fluid

Compatibility

Designed for through-hole threading of 1-8 UNC right-hand threads in steel. Compatible with CNC tapping centers, drill presses, and hand tap drivers that accept a shank diameter of 0.8 inches. Series 3901 spiral point geometry.

Installation Notes

Installation of this tap should be performed by a qualified machinist following standard threading procedures. Secure the workpiece fully before engaging the tap, and apply a suitable cutting fluid to reduce heat and extend tool life when tapping steel. Ensure the tap is aligned perpendicular to the workpiece to avoid thread lead errors or tool breakage. Follow OSHA and shop-specific lockout/tagout procedures when operating tapping equipment.