Osg 1705101 Spiral Flute Tap 5/8-18 Unf 4 Flutes

Product Description

The OSG 1705101 is a spiral flute tap designed for cutting 5/8-18 UNF internal threads in challenging workpiece materials. It features four right-hand spiral flutes with a 15-degree helix angle that evacuates chips up and out of the hole — making it well suited for blind-hole tapping where chip packing is a concern. The modified bottoming chamfer allows threading close to the bottom of a hole with minimal clearance. A steam oxide coating reduces friction and helps resist built-up edge during cutting. The 2B class of fit produces standard commercial-tolerance threads, and the H5 thread limit keeps tolerances tight for consistent fit across production runs.

This tap is intended for use in alloy steel, stainless steel, hardened steel, titanium, and high-nickel alloy workpieces — materials common in aerospace, defense, oil and gas, and precision machining environments. The powdered metal construction provides the toughness and wear resistance needed when threading hard or abrasive stock. It is used in CNC machining centers, turret lathes, and manual tapping operations where a 5/8-18 UNF thread form is required. The Series 313 designation places it within OSG's standard spiral flute tap product line.

Key Features

• 5/8-18 UNF thread form with H5 thread limit for tight, consistent 2B-class tolerances
• 4 right-hand spiral flutes at 15-degree helix angle for upward chip evacuation in blind holes
• Modified bottoming chamfer for threading close to hole bottom
• Powdered metal construction for increased toughness in hard and abrasive materials
• Steam oxide coating reduces friction and minimizes built-up edge
• Rated for alloy steel, stainless steel, hardened steel, titanium, and high-nickel alloys

Compatibility

Designed for cutting 5/8-18 UNF right-hand internal threads in alloy steel, stainless steel, hardened steel, titanium, and high-nickel alloy workpieces. Coolant-through is not supported on this tap.

Installation Notes

Installation is performed by machinists and tooling technicians using a compatible tap holder or tapping attachment sized for the 0.48-inch shank diameter. Ensure the workpiece is securely fixtured and the pilot hole diameter is correct for a 5/8-18 UNF tap before starting. Use appropriate cutting fluid or tapping compound for the workpiece material, particularly when threading stainless steel, titanium, or high-nickel alloys. Inspect the tap for wear or chipping between uses, as hard materials accelerate tool degradation.