Kennametal 1521789 Indexable Insert Drill 7/8 Inch 4xd

Product Description

The KENNAMETAL 1521789 is a straight-shank indexable insert drill built for production drilling in metal cutting applications. It accepts two DFT-style inserts and delivers a maximum drill depth of 3.5 inches (88.9mm) at a 4xD depth-to-diameter ratio. The body is constructed from steel, with a 1-inch Weldon Flat and Flange shank diameter and an overall length of 8 inches. Coolant-through capability is supported via axial concentric entry, with a body-side coolant port threaded at 1/8-27 and a shank-end port at 1/4-18. This drill is suited for CNC machining environments where repeatable hole quality and insert replaceability are priorities.

The 1521789 is designed for general-purpose drilling in production machining. Its 7/8-inch nominal drill diameter and 4xD capability make it a practical choice for through-hole and blind-hole work across a range of ferrous and non-ferrous materials. The straight shank with Weldon Flat accommodates standard side-lock toolholders common on machining centers and CNC lathes with live tooling. The DFT insert platform allows quick insert changes at the machine without removing the body from the spindle.

Key Features

• 4xD drill depth ratio with 3.5-inch (88.9mm) maximum drill depth
• Accepts two DFT0303 indexable inserts for economical cutting edge management
• Coolant-through design with axial concentric entry for chip evacuation and tool life
• 1-inch Weldon Flat and Flange shank for secure side-lock toolholder clamping
• Right-hand cutting direction; general-purpose tool performance rating
• Insert lock screw: M2.5-0.45 x 5.9 T8 Torx drive

Compatibility

Compatible with DFT-style inserts, insert size code 0303, compatible insert designation DFT0303. Designed for use in the KENNAMETAL DFT series drill body platform.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician. Secure the Weldon Flat shank in a properly rated side-lock toolholder and verify runout before production use. Ensure coolant lines are connected and flow is confirmed before drilling to protect insert edges and aid chip evacuation. Follow the machine tool manufacturer torque and clamping specifications for the toolholder - do not use insert seating torque values not provided in the KENNAMETAL tool documentation.