H R Manufacturing HR-487-P Soft Lathe Chuck Jaw 8 in

Product Description

The H R MANUFACTURING HR-487-P is a soft lathe chuck jaw with a tongue and groove interface, designed for use in manual and CNC lathe setups where custom boring to size is required. Machined from 1018 steel, this jaw is compatible with 8-inch chuck bodies and provides a stable, repeatable grip on workpieces. The tongue and groove design locks the jaw securely to the chuck master jaw, minimizing movement under cutting loads. At 3-15/16 inches overall length and 1-1/2 inches overall width, it provides solid stock for boring to a specific diameter or profile. Weighing approximately 4.67 pounds, the jaw is substantial enough for demanding turning operations.

This jaw is intended for use on engine lathes, turret lathes, and CNC turning centers equipped with 8-inch three-jaw or four-jaw chucks that use tongue and groove master jaw interfaces. It is a soft jaw, meaning it arrives unmachined at the gripping face and must be bored in place by the machinist to match the specific workpiece geometry or diameter. This process ensures concentricity and is standard practice in production and job-shop turning environments. Licensed machinists and toolroom technicians are the primary installers.

Key Features

• Tongue and groove interface for secure, repeatable seating on compatible chuck master jaws
• 1018 steel construction offers good machinability for in-place boring without excessive tool wear
• Square jaw shape provides uniform clamping geometry across the workpiece contact face
• 0.500-inch slot width and 0.313-inch groove width for precise interface fit
• 1.750-inch distance between mount hole centers for accurate bolt pattern alignment
• Soft construction allows custom boring to workpiece diameter for improved concentricity and grip

Compatibility

Compatible with lathe chucks having a maximum and minimum chuck diameter of 8.0 inches and a tongue and groove master jaw interface. Verify slot width, groove width, and mount hole spacing against your chuck specifications before installation.

Installation Notes

Soft jaws must be bored in place after mounting to the chuck to achieve proper concentricity. Power down the lathe and lock out the spindle drive before removing or installing chuck jaws. Use the correct cap screws and torque to the chuck manufacturer's specifications. Bore the jaw gripping face with the jaws lightly clamped against a ring or plug of appropriate diameter to simulate clamping force during use.