Osg 3145803 Straight Flute Tap 8-32 Unc Cobalt Nitride

Product Description

The OSG 3145803 is a straight flute tap designed to cut 8-32 UNC internal threads in plastic and other compatible materials. Built from cobalt high-speed steel with a nitride coating, it delivers extended tool life in production and maintenance tapping applications. The plug chamfer style eases thread starting, while the 4-flute geometry supports chip evacuation in through-hole and short blind-hole work. Overall length is 3/4 inch with a shank diameter of 0.168 inches. This tap is sized for use in hand-tap drivers, tapping heads, or CNC threading cycles by machinists, maintenance mechanics, and tool-room technicians.

This tap is suited for threading 8-32 UNC holes in plastic workpieces and similar non-ferrous or soft materials. The plug chamfer makes it appropriate for through-hole applications or blind holes with sufficient thread runout. It fits standard tap holders sized for the 0.168-inch shank diameter and is commonly used in light manufacturing, electronics assembly, and general maintenance shops where 8-32 fastener threads are required.

Key Features

• 8-32 UNC thread form, 2B class of fit for standard tolerance internal threads
• Cobalt construction for improved heat and wear resistance over standard HSS
• Nitride coating reduces friction and extends service life
• 4-flute straight flute design for chip control in through-hole tapping
• Plug chamfer for easier thread engagement and starting
• Right-hand thread direction for standard tapping operations

Compatibility

Designed as a direct-fit replacement tap for standard 8-32 UNC tapping applications using holders sized for a 0.168-inch shank diameter, part of OSG Series 114.

Installation Notes

This tap is installed and operated by machinists or maintenance technicians using a tap wrench, tapping head, or CNC spindle with appropriate speed and feed settings for the workpiece material. Ensure the workpiece is securely fixtured before tapping. Use cutting fluid or tapping compound as appropriate for the material to reduce heat buildup and extend tap life. Do not force the tap if resistance increases unexpectedly, as cobalt tools can fracture under side-loading or misalignment.