TOP-TOOL Professional 3-Jaw Self-Centering Lathe Chuck, 500mm / 20-Inch, Clamping Range 25–500 mm (0.98–19.69 in), Two-Piece Jaws (Master + Reversible Top Jaws), Pre-Mounted Set, T-Key, Plain Back

Professional 500mm / 20-Inch 3-Jaw Self-Centering Lathe Chuck (Two-Piece Jaws (Master + Reversible Top Jaws))

Built for metal lathes, wood lathes, drill presses, milling machines, CNC machining centers, grinders, and other equipment that needs self-centering workholding. The TOP-TOOL 500 mm chuck delivers rigid gripping when mounted with the correct adapter plate or fixture. HT300 cast iron body, AISI 5140 scroll and bevel gears, AISI 1045 jaws. Overall clamping envelope 25–500 mm (0.98–19.69 in) across the three modes below.

Premium Materials & Hardening

Clamping ranges

Outside clamping with solid outside jaws (standard setup): 25–280 mm gripping on the outside diameter.

Inside support / expanding with the same outside jaws: 150–500 mm internal gripping (boring-style holding).

Outside clamping with solid inside (reverse) jaws: 150–500 mm for large-diameter OD work.

Summary: overall envelope 25–500 mm (0.98–19.69 in) depending on jaw configuration.

Key Features

• Heavy-Duty HT300 Cast Iron: High mass and damping for large workpieces and heavy cuts.
• Hardened Scroll & Gears: AISI 5140 scroll (HRC 43–48) and bevel gears (HRC 45–50).
• Hardened Jaws (HRC 52–58): AISI 1045 for grip and wear resistance.
• Guaranteed Precision: Checked with four different test bars as part of our acceptance process. Repeatability ≤0.05 mm (0.002").
• Plain Back Mount: D1 = 440 mm locating register, recess depth h = 6.5 mm; D2 = 465 mm bolt circle; 6× M16 mounting holes. Machine your adapter to match D1/D2. Adapter plate not included.
• Two-Piece Jaw System: Master jaws with reversible top jaws pre-mounted—configure for OD or ID work per the jaw instructions. No second full jaw kit is included in the box (not the same packaging as solid-jaw models).
• T-Key Included.

Jaw type

This listing uses two-piece jaws (master jaws + top jaws). For solid outside/inside jaw sets, see our other listings.

Technical Specifications

Dimensions per factory charts Dimensions.webp / Dimensions-2.webp; clamping per clamping-range chart.

Error-Free Jaw Installation

Jaws and body are numbered (1, 2, 3) so each jaw matches its slide—faster setup and better concentricity.

Versatile Applications

• Metal lathe: Turning, facing, drilling, boring (with correct adapter).
• Wood lathe: Where spindle and safety requirements allow.
• Milling machine / machining center: On suitable arbors or fixtures.
• Drilling machine: Concentric holding.
• CNC: Production use where applicable.
• Grinder: When speed-rated and safely mounted.

Compatibility Guide

Machine swing or envelope must clear the chuck body and fully opened jaws. Plan a comfortable margin above nominal diameter D. Your adapter must match D1, D2, and the bolt pattern listed above.

Maintenance

Clean regularly. Apply molybdenum disulfide (MoS₂) grease to the scroll and bevel gears.

Safety

Never run with the chuck key engaged. Observe safe speeds for chuck size and workpiece balance.