Seco 74069656 Turning Insert Dnmp 431-MF1 890 Carbide

Product Description

The SECO 74069656 is a solid carbide, uncoated turning insert in the DNMP-MF1 series, designed for precision metal cutting in demanding industrial turning applications. It features a 55-degree diamond shape (Insert Shape Code D) with a negative rake angle and a honed cutting edge. The inscribed circle measures 0.5 inches, the corner radius is 0.0157 inches (1/64 inch), and the insert thickness is 0.1874 inches. With four cutting edges and an MF1 chip breaker geometry, this insert is suited for high-efficiency material removal where edge stability and controlled chip flow are required. It is installed by machining professionals and toolroom technicians on CNC lathes and turning centers.

This insert is optimized for primary use on superalloys and titanium (ISO workpiece material code S), with secondary compatibility across steel (M), cast iron (K), non-ferrous materials (N), and hardened materials (H). Typical applications include turning, facing, boring, and back turning operations. The MF1 chip breaker geometry is engineered for light-to-medium finishing passes on difficult-to-machine materials where tight tolerances and surface finish are critical. It conforms to both ANSI and ISO standards, with an ISO code of DNMG150404-MF1 and an industry standard number of DNMP431-MF1. Material grades S10 and S20 classify this insert for cutting tool grade selection in superalloy and titanium work.

Key Features

• Solid carbide, uncoated (bright finish) construction for use in superalloys and titanium where coatings may cause built-up edge
• 55-degree diamond insert shape with negative rake for increased edge strength and stability
• MF1 chip breaker geometry optimized for light-to-medium finishing cuts with controlled chip evacuation
• Four usable cutting edges per insert for extended tool life per unit
• Compatible with clamp, pin, and lever lock holding methods for broad toolholder adaptability
• Multi-use geometry supports turning, facing, boring, and back turning operations

Compatibility

Designed for use in DNMP-style toolholders that accept a 55-degree diamond insert with a 0.2028-inch hole diameter, clamp, pin, or lever lock holding method, and a clearance code N with tolerance code M. Compatible toolholders must accommodate an insert length of 1.2204 inches and a maximum depth of cut up to 0.5945 inches. Conforms to ANSI and ISO standards; ISO code DNMG150404-MF1.

Installation Notes

Installation is performed by a qualified machinist or toolroom technician on a CNC lathe or manual turning center. Ensure the machine spindle is fully stopped and the turret is indexed to a safe position before seating or replacing inserts. Use the appropriate torque wrench and clamp screw per the toolholder manufacturer's specifications when securing the insert via clamp, pin, or lever lock. Inspect the insert pocket and seating surfaces for chips or debris before installation to ensure proper seating and edge alignment.