1995 Harrison M390 GH Geared Head Lathe

15.7" / 23" x 50" Gap Bed | S/N G70065 | High-Precision Toolroom Grade

Overview

The Harrison M390 GH is built for shops where accuracy is non-negotiable. Known for its "standard of the industry" status, this machine is guaranteed by the manufacturer to turn within 0.0001" TIR. This 1995 unit features a robust 7.5 HP motor and a wide 2.125" spindle bore, offering significantly more capacity than the smaller M300 models while maintaining the same delicate "feel" for precision work.

This is the Gap Bed version, allowing for a 23" swing for large-diameter work, making it one of the most versatile machines in its footprint.

Technical Specifications

• Year of Manufacture: 1995
• Swing Over Bed: 15.75" (400 mm)
• Swing in Gap: 23" (585 mm)
• Distance Between Centers: 50" (1250 mm)
• Spindle Bore: 2.125" (54 mm)
• Spindle Speeds (16): 25 – 2,000 RPM
• Spindle Nose: D1-6 Camlock
• Spindle Taper: #4 Morse Taper
• Main Drive Motor: 7.5 HP, 230/460V, 3-Phase
• Bed Width: 12.5" (Induction Hardened & Ground)
• Tailstock Taper: #5 Morse Taper
• Threading (Inch): 2 – 56 TPI (56 Pitches)
• Threading (Metric): 0.2 – 14 mm (51 Pitches)
• Machine Weight: Approx. 3,300 lbs

Key Features & Dealer Benefits

• Precision Gamet Spindle Bearings: High-precision tapered roller bearings ensure superior surface finishes and extreme repeatability for aerospace and mold-and-die work.
• Forced Lubrication System: Unlike splash-lubricated lathes, the M390 features a pumped oil bath for the headstock gears and shafts, significantly reducing heat and wear during high-speed operation.
• Electromagnetic Spindle Brake: Allows for nearly instantaneous stopping of the spindle, improving cycle times and operator safety.
• Modern Control Dial: Features a user-friendly 8-position rotary dial and three levers for quick feed and thread selection—no complex charts or gear swaps required.
• Removable Gap Block: Increases swing capacity by nearly 50% for one-off large diameter jobs like flanges or pump impellers.
• One-Shot Apron Lubrication: A manual pump ensures the hardened ways and carriage remain properly oiled with every shift.