Tweco 1040-1133 Mig Gun 400A 12 Foot Miller

Product Description

The TWECO 1040-1133 is a Professional No. 4 Classic Series air-cooled MIG gun rated at 400 amps with a 60% duty cycle using CO2 gas. It accepts wire sizes from 0.035 inches to 0.045 inches and includes a 12-foot lead cable with a Miller-style rear connection. The oval-shaped handle is constructed from high-impact, crush-resistant plastic and is balanced to pivot at its center, reducing operator fatigue during extended use. A 60-degree metal jacket conductor tube features a three-layer construction — copper tube, silicon-resin glass insulator, and metal jacket — and swivels a full 360 degrees around the handle for flexible positioning. Licensed HVAC technicians, pipefitters, and professional welders in fabrication and industrial maintenance environments are the primary users.

The 1040-1133 is suited for semi-automatic MIG welding in medium- to heavy-duty fabrication settings including production shops, maintenance and repair operations, and industrial manufacturing environments. The Miller-style rear connection makes it a direct fit for wire feeders using that interface. Interchangeable front-end consumables are compatible with both the Tweco Spray Master series and the Tweco Professional No. Series, lowering inventory requirements for shops running multiple guns.

Key Features

• 400 amp output rating with 60% duty cycle at CO2 gas
• Accepts wire diameters from 0.035 inches to 0.045 inches
• 12-foot lead cable with Miller-style rear connection and fully insulated Mig-Kwik quick-connect at the wire feeder
• Three-layer conductor tube construction (copper tube, silicon-resin glass insulator, metal jacket) with full 360-degree swivel
• Silver-plated trigger contacts with self-cleaning action on each engagement and disengagement
• Steel spring strain relief at handle rear minimizes wire feed issues; split-half handle allows field repair without additional connectors
• Gun hanger at bottom of handle for safe resting when not in use

Compatibility

Designed for use with Miller-style wire feeders. Front-end consumables are interchangeable with the Tweco Spray Master series and Tweco Professional No. Series guns, allowing shared consumable inventory across compatible platforms.

Installation Notes

Installation and setup should be performed by a qualified welding technician or experienced fabrication professional. Disconnect and power down the wire feeder before making or breaking the rear connection. Verify that the wire feeder drive rolls and liner are matched to the selected wire diameter before feeding wire through the gun. Follow the equipment manufacturer's guidelines and applicable workplace safety codes when routing the lead cable to avoid kinking or excessive bending at the strain relief.

Technical Specifications

• Amperage: 400 amps
• Duty Cycle: 60% (CO2 gas)
• Wire Size Range: 0.035 inches to 0.045 inches
• Lead Cable Length: 12 feet
• Rear Connection Style: Miller
• Conductor Tube Angle: 60 degrees
• Cooling Method: Air-cooled
• Weight: 10.75 pounds
• Length: 23.2 inches
• Width: 3.1 inches
• Height: 14.3 inches

Standard Information

• Brand: TWECO
• Manufacturer Part Number: 1040-1133