Osg 1430600 Spiral Flute Tap 5/16-24 Unf 3 Flute Hss

Product Description

The OSG 1430600 is a spiral flute tap designed for cutting 5/16-24 UNF internal threads in a range of ferrous and non-ferrous metals. Built from high-speed steel (HSS) with a bright, uncoated finish, it features a plug chamfer and a 50-degree helix angle that efficiently evacuates chips upward out of the hole during through-hole and blind-hole tapping operations. The 3-flute design provides strong chip control at moderate cutting speeds. With a 3B class of fit and H3 thread limit, this tap produces threads within standard commercial tolerance for most fastener and assembly applications. Licensed HVAC, plumbing, and mechanical trades routinely stock this size for repair and fabrication work.

The OSG 1430600 is suited for tapping aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. Its right-hand spiral flute geometry and plug chamfer make it a common choice for production and maintenance applications where a standard starting chamfer is acceptable. The Series 107 designation places it within OSG's general-purpose HSS tap line, appropriate for both manual and machine tapping setups in shop and field environments.

Key Features

• 5/16-24 UNF right-hand thread, 3B class of fit with H3 thread limit for standard commercial tolerance
• 50-degree right-hand spiral helix angle for upward chip evacuation in through and blind holes
• 3-flute plug chamfer geometry for positive thread entry and consistent chamfer lead
• High-speed steel construction, bright uncoated finish - no coating buildup risk on aluminum or cast materials
• Coolant-through: No - compatible with flood coolant or cutting oil applied externally
• Compact overall length of 2.719 inches suits both hand-tap wrenches and machine spindles

Compatibility

Designed for use in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. Suitable for manual tapping with a T-handle or tap wrench and for machine tapping on drill presses, CNC machining centers, or tapping heads where a standard plug-chamfer spiral flute tap is specified.

Installation Notes

This tap is installed by machinists, millwrights, pipefitters, and maintenance mechanics working in fabrication, repair, or field-service environments. Always drill the correct tap drill size for 5/16-24 UNF prior to tapping, and ensure the workpiece is securely clamped before starting. Apply a suitable cutting oil or tapping fluid to extend tool life and improve thread finish, particularly in steel and cast iron. Reverse the tap periodically during hand tapping to break and clear chips and prevent tap breakage in deep or blind holes.