Kennametal 1521790 Indexable Insert Drill 3/4 in 4xd

Product Description

The KENNAMETAL 1521790 is a straight-shank indexable insert drill designed for production drilling applications in metalworking environments. Built to the DFT series standard, it accepts two DFT0303 inserts and delivers a maximum drill depth of 3 inches (76.2 mm) at a 4xD depth-to-diameter ratio. The 3/4-inch shank features a Weldon flat and flange configuration, providing positive rotational drive and repeatable tool positioning. Overall length is 6.5 inches, with a body length of 4.5 inches and a flute length of 3 inches. The steel body supports coolant-through capability via axial concentric entry, keeping the cutting zone clear and extending insert life during deep-hole operations. This tool is installed and run by machinists and CNC operators in job shop and production environments.

The 1521790 is suited for general-purpose right-hand drilling in ferrous and non-ferrous materials on CNC machining centers and milling machines where a Weldon-flat straight shank is required. The 4xD reach makes it practical for through-holes and blind-holes in workpieces up to 3 inches thick. Maximum drill diameter reaches 0.850 inches depending on insert selection. Compatible insert size code is 0303, fitting standard DFT-style inserts available in multiple grade and geometry options for matching the insert to the workpiece material.

Key Features

• 4xD depth-to-diameter ratio with 3-inch maximum drill depth (76.2 mm)
• Accepts two DFT0303 indexable inserts for dual cutting-edge engagement
• Weldon flat and flange shank for positive drive in ER and side-lock holders
• Coolant-through design with axial concentric entry; body and shank coolant ports threaded 1/8-27
• Right-hand cutting direction; general-purpose tool application
• Steel body construction; 6.5-inch overall length

Compatibility

Compatible with DFT drill style tooling systems. Takes DFT0303 insert style inserts (insert size 0.156 x 0.116 inches / 3.97 x 2.95 mm). Insert lock screw specification is M2.5-0.45 x 5.9 T8. Consult KENNAMETAL DFT series insert grade and geometry charts to match insert selection to workpiece material.

Installation Notes

Installation is performed by qualified machinists or CNC setup technicians. Ensure the machine spindle is fully stopped and locked out before mounting or removing the tool. Seat the Weldon flat shank fully into the holder before tightening the drive screw to the holder manufacturer's specified torque. Verify coolant port alignment with the machine spindle coolant supply before running coolant-through at operating pressure; use the 1/8-27 threaded ports with appropriate fittings if direct plumbing is required.