Osg 1650505808 Spiral Flute Tap 5/16-32 Unf Ticn Coated

Product Description

The OSG 1650505808 is a spiral flute tap designed for threading 5/16-32 UNF holes in a wide range of ferrous and non-ferrous materials. Built from powdered metal and finished with a TICN (Titanium Carbonitride) coating, this tap delivers hardness and lubricity suited for demanding production and job-shop environments. It carries a 45-degree helix angle that efficiently evacuates chips upward out of the hole — the defining advantage of a spiral flute design. The 2B class of fit and H3 thread limit ensure dimensional accuracy that meets standard fastener assembly requirements. Overall length is 3.15 inches with a thread length of 0.444 inches.

This tap is suited for right-hand threading operations in CNC machining centers, drill presses, and manual tapping setups where blind or shallow-depth holes require a semi-bottoming chamfer to thread close to the bottom of the bore. The semi-bottoming (modified bottoming) chamfer provides a short lead-in, making it appropriate where a standard plug tap cannot reach deep enough but a full bottoming tap is not required. Compatible material applications include alloy steel, aluminum, cast aluminum, cast iron, hardened steel, high-carbon steel, low-carbon steel, medium-carbon steel, and stainless steel. Tapping depth reaches 35.00 mm.

Key Features

• 45-degree right-hand spiral flute geometry evacuates chips upward — ideal for blind hole tapping
• TICN coating increases surface hardness and reduces friction for extended tool life
• Powdered metal construction provides uniform grain structure and improved wear resistance over standard HSS
• Semi-bottoming (modified bottoming) chamfer allows threading closer to the bottom of a blind hole than a plug tap
• H3 thread limit and 2B class of fit ensure accurate thread form for standard fastener assembly
• No coolant-through design — suitable for use with cutting oil or flood coolant applied externally

Compatibility

Designed for 5/16-32 UNF threading applications across alloy steel, aluminum, cast aluminum, cast iron, hardened steel, high-carbon steel, low-carbon steel, medium-carbon steel, and stainless steel workpieces. Part of OSG Series 16505.

Installation Notes

Installation is performed by machinists and tooling technicians using standard tap holders, floating collets, or rigid tapping adapters matched to the shank and square dimensions. Ensure the spindle speed and feed rate are appropriate for the workpiece material and tap diameter before engaging the cut. Apply a suitable cutting fluid or tapping compound to the tap and workpiece prior to use to reduce heat and extend tool life. Inspect the tap for wear or chipping between uses — a damaged tap can destroy the threaded bore and the workpiece.