Osg 2833400 Spiral Point Plug Tap 5/8-18 Unf 3 Flutes

Product Description

The OSG 2833400 is a spiral point plug tap designed for machine tapping of through-hole threads in a wide range of ferrous and non-ferrous materials. Built from vanadium high-speed steel with a bright finish, this tap produces 5/8-18 UNF right-hand threads to a 3B class of fit with an H3 thread limit. The spiral point geometry pushes chips forward ahead of the tap rather than packing them into the flutes, making it well suited for through-hole applications where chip evacuation is critical. With three flutes and a plug chamfer, it balances cutting speed with rigidity across a variety of CNC and manual machine tapping setups. Overall length is 3.811 inches with a thread length of 1.91 inches.

This tap is used in production and maintenance machining environments where 5/8-18 UNF through-hole threads are required. Suitable material applications include aluminum, low-carbon steel, medium-carbon steel, high-carbon steel, alloy steel, die steel, stainless steel, and cast iron. The plug chamfer makes it appropriate as a starter tap or as the sole tap in through-hole operations. Machinists, toolroom technicians, and maintenance mechanics working in industrial, aerospace, and general fabrication settings will find this tap applicable across a broad range of base metals.

Key Features

• Spiral point geometry pushes chips forward, ideal for through-hole tapping
• 5/8-18 UNF thread form, 3B class of fit, H3 thread limit for consistent tolerance control
• Vanadium high-speed steel construction for improved wear resistance over standard HSS
• Plug chamfer provides 3-5 thread lead-in for general-purpose through-hole use
• Bright finish with no coating — compatible with a wide range of cutting fluids
• Right-hand cut, no coolant-through, non-interrupted thread form

Compatibility

Designed for through-hole machine tapping of 5/8-18 UNF threads in aluminum, hardened steel, stainless steel, high-carbon steel, low-carbon steel, medium-carbon steel, alloy steel, die steel, and cast iron. Not intended for blind-hole applications where chip evacuation forward is not possible.

Installation Notes

This tap is installed by machinists or toolroom technicians in a standard tap holder, tapping head, or rigid CNC tapping chuck sized for the 0.48-inch shank diameter. Power down or de-energize all machine motion before changing tooling. Use an appropriate cutting fluid or tapping compound for the workpiece material to extend tool life and achieve proper thread finish. Verify workpiece is securely fixtured and pilot hole diameter is correct for 5/8-18 UNF before beginning the tapping cycle.