Osg 1727001 Spiral Point Tap 4-48 Unc 2 Flute Plug

Product Description

The OSG 1727001 is a spiral point plug tap designed for threading operations in ferrous and alloy materials across industrial and maintenance machining environments. Built from vanadium high speed steel with a steam oxide coating, it produces right-hand internal threads in the 4-48 UNC designation. The 2-flute spiral point geometry pushes chips forward ahead of the cutting zone, keeping the flutes clear during through-hole tapping. With a thread limit of H4 and an overall length of 1.874 inches, this tap suits precision threading in production and repair settings. It is installed by machinists, toolroom technicians, and maintenance professionals working with tapping machines, drill presses, or hand tap holders.

This tap is suited for threading through-holes in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel. Its plug chamfer provides a gradual lead-in, making it appropriate for starting in a pre-drilled hole without requiring a taper tap first. The steam oxide finish provides mild lubricity and corrosion resistance, which can extend tool life in moderate-duty applications. It is commonly used in HVAC equipment assembly, electrical panel fabrication, and general sheet metal and structural fastener work where 4-48 UNC threads are specified.

Key Features

• Spiral point geometry pushes chips forward for clean through-hole tapping
• Steam oxide coating adds lubricity and reduces galling tendency
• Plug chamfer allows direct engagement in pre-drilled through-holes
• H4 thread limit suits close-tolerance UNC thread production
• Compatible with hardened steel, low-carbon steel, medium-carbon steel, and stainless steel
• Right-hand cut, no coolant-through requirement

Compatibility

Designed for cutting 4-48 UNC right-hand internal threads in through-hole applications across hardened steel, low-carbon steel, medium-carbon steel, and stainless steel workpieces.

Installation Notes

A licensed machinist or toolroom technician should select the correct tap drill size for the 4-48 UNC thread before beginning. Secure the workpiece fully before tapping and apply appropriate cutting fluid to prolong tool life, particularly when threading stainless steel. Use a calibrated torque-limiting tap holder where possible to reduce the risk of tap breakage in small-diameter taps. Never reverse a spiral point tap rapidly under load - back off gradually to clear chips and avoid binding.