Osg 1733905 Spiral Flute Tap 3/4-16 Unf Tin Vanadium Hss

Product Description

The OSG 1733905 is a spiral flute tap designed for cutting 3/4-16 UNF internal threads in ferrous materials including stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel. Built from vanadium high-speed steel and coated with titanium nitride (TiN), the tap delivers extended tool life and reduced friction during the threading operation. It features a modified bottoming chamfer, four right-hand spiral flutes at a 45-degree helix angle, and an H3 thread limit with a 3B class of fit. The 45-degree helix promotes efficient chip evacuation in blind-hole applications. This tap is installed by machinists and tool-and-die professionals working in precision machining environments.

This tap is suited for blind-hole and through-hole threading in applications where a fine unified thread form is required. The modified bottoming chamfer allows threading closer to the bottom of a blind hole than a standard plug chamfer. Typical use cases include threading hydraulic fittings, fastener holes in medium and high-carbon steel components, and stainless steel assemblies where thread accuracy and fit are critical. The TiN coating is particularly beneficial when tapping stainless steel, which tends to work-harden during cutting.

Key Features

• 3/4-16 UNF right-hand thread, H3 thread limit, 3B class of fit for precision thread control
• 45-degree right-hand spiral flutes promote upward chip evacuation in blind-hole applications
• Modified bottoming chamfer allows threading near the bottom of blind holes
• TiN coating reduces friction and improves wear resistance, especially in stainless and carbon steels
• Vanadium high-speed steel substrate provides toughness and heat resistance
• Series 303 design — no coolant-through feature; suited for conventional flood or manual lubrication

Compatibility

Designed for threading stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel workpieces requiring a 3/4-16 UNF thread form. Fits standard tap holders and chucks accepting the shank and square dimensions of this tap series.

Installation Notes

This tap is installed by machinists using a tap wrench, tapping head, or CNC rigid tapping cycle. Always secure the workpiece and ensure the tap is properly aligned to the pre-drilled hole before applying torque. Use an appropriate cutting fluid or tapping compound, particularly when working with stainless steel, to prevent galling and work-hardening. Follow shop-standard procedures and applicable safety guidelines when operating tapping equipment.