This is a 3/4"-10 UNC right-hand split die manufactured from high-speed steel (HSS M2) and intended for cutting and repairing external Unified Coarse (UNC) threads on studs, bar and bolts. Its primary use is to create or restore 3/4" diameter, 10 threads-per-inch external threads where a robust imperial coarse thread form is required; it is designed for hand use in a die stock and can also be used in compatible machine die holders where appropriate speeds and feeds are observed.

The tool is supplied as a 1½" round split die body with an adjustable split and clamp screw to allow slight size correction and easy removal of the die from the workpiece. Thread form is 3/4"-10 UNC (Unified National Coarse), right hand, 10 TPI, conforming to the UNC profile as defined by ANSI/ASME B1.1; the die body follows common DIN/ISO dimensional conventions for round split dies. Material grade is M2 high-speed steel for good hardness retention and wear resistance, with a black oxide finish to reduce friction and give additional mild corrosion protection. Cutters are ground to the correct thread profile and supplied with a centre chamfer to aid starting. For stainless and tougher alloys use appropriate cutting fluid and reduced feed to prolong tool life.

Typical applications include general engineering, plant maintenance, heavy fabrication, agricultural and construction machinery repairs, automotive restoration and site re-threading where UNC fasteners are used. The split design makes this die especially useful for repairing damaged external threads, sizing slightly out-of-tolerance studs and finishing threads on turned bar where a small adjustment to the cut is required.

Key benefits are the durability and heat resistance of M2 HSS, the adjustability of the split die for precise sizing and repair work, and direct compatibility with standard 3/4"-10 UNC bolts and studs (ANSI/ASME B1.1). The black oxide finish reduces corrosion and improves chip flow compared with untreated tooling.

Duchy Fasteners holds a comprehensive range of HSS split dies and die stocks in imperial sizes; this item is available individually or in multi-packs—please contact us for current stock sizes and pack quantities. Product code DIEC0075.