10401689 - Tweco Classic 4 MIG Gun, 400A, 15ft, Lincoln Connection

Technical Specifications and Performance

The Tweco Classic No. 4 MIG Gun (SKU: 1040-1689) is a premium air-cooled GMAW/FCAW torch designed for high-performance industrial welding. It features a Lincoln-style rear connection, making it fully compatible with Lincoln Electric wire feeders that utilize the standard direct-plug configuration. This gun is rated for 400 Amps at 60% Duty Cycle using CO2 gas, making it suitable for wires ranging from .035" to .045" (0.9mm - 1.2mm) in its standard configuration, though it can accommodate wires up to 5/64" (2.0mm) with the appropriate liner and tip changes.

The assembly features a 15-foot (4.5m) cable constructed with high-quality copper stranding to minimize voltage drop and heat buildup. The Classic 4 handle is ergonomically designed to provide a comfortable grip while housing a heavy-duty trigger switch rated for millions of cycles. The metal-jacketed conductor tube (gooseneck) is insulated to prevent electrical shorts and is rotatable in some configurations to aid in accessing difficult joints.

Consumable compatibility is a key feature of this unit. It utilizes the standard Tweco 14 Series contact tips, 54A gas diffusers, and 24 Series adjustable slip-on nozzles. The use of a coarse thread nozzle assembly ensures a tight fit that resists spatter buildup and allows for easy cleaning. The internal liner is a 44 Series steel wound liner, known for its kink resistance and smooth wire feeding properties. For maintenance professionals and welding engineers, the Tweco Classic 4 represents a low-TCO (Total Cost of Ownership) solution due to its rugged repairable components and inexpensive consumables.

Key Technical Data

• Process: MIG (GMAW) & Flux Cored (FCAW)
• Cooling: Air Cooled
• Amperage: 400A (CO2) / 300A (Mixed Gas)
• Connection: Lincoln Direct Plug
• Standard Wire Size: .035" - .045"