Accupro 1P062050000000 Drill Chuck Lead Screw MT4 R8

Product Description

The ACCUPRO 1P062050000000 is a replacement lead screw designed for use with 5/8 inch MT4 and R8 drill chucks. The lead screw is the central retention fastener that draws the chuck arbor into the spindle taper and holds it securely during drilling operations. Without a properly functioning lead screw, the chuck cannot be seated or removed safely. This part is used by machinists, tool and die technicians, and drill press operators who are refurbishing or reassembling drill chucks on manual mills, drill presses, and similar machine tool spindles. At 0.13 pounds, it is a compact, precision-machined component.

This lead screw is compatible with 5/8 inch drill chucks mounted on MT4 (Morse Taper 4) and R8 spindle interfaces. These spindle types are common on knee mills, Bridgeport-style milling machines, and heavy-duty drill presses found in production shops and maintenance departments. The part is typically needed when a chuck is being disassembled for cleaning, when the original lead screw is damaged or stripped, or when a chuck is being transferred to a different machine spindle of the same taper specification.

Key Features

• Designed specifically for 5/8 inch MT4 and R8 drill chucks
• Functions as the central retention fastener for taper-mount drill chucks
• Lightweight at 0.13 pounds for easy handling during reassembly
• Sold individually — one lead screw per package
• Suitable for refurbishment and replacement applications on machine tool spindles

Compatibility

Designed for use with 5/8 inch MT4 and R8 taper drill chucks. Verify chuck model and spindle taper specification before ordering to confirm fitment.

Installation Notes

Installation is performed by machinists or qualified machine tool technicians. Before replacing the lead screw, power down and lock out the machine at the main disconnect in accordance with OSHA lockout/tagout procedures. The lead screw threads into the draw bar or chuck arbor — do not overtighten, as stripping the threads will damage the chuck or spindle. Confirm the taper seat is clean and free of chips or burrs before seating the chuck assembly.