81F02 - Lenco AF-3 Style 500A Stick Electrode Holder

Technical Overview: AF-3 Series 500A Electrode Holder

The AF-3 Electrode Holder is a high-capacity manual electrode holder designed for Shielded Metal Arc Welding (SMAW) at currents up to 500 Amperes. This model is widely recognized in the industry for its robust design and efficient thermal management. It is specifically engineered to accommodate large diameter electrodes, with a jaw capacity capable of securely gripping rods up to 3/8 inch (9.5 mm). The jaw design allows for multi-angle electrode positioning, facilitating access to tight joints and enabling optimal torch angles for various welding positions.

Material & Conductivity:
The upper and lower tongs are manufactured from a high-strength aluminum alloy. This material choice provides a high strength-to-weight ratio and excellent electrical conductivity, which is critical for minimizing resistance heating at the jaw-electrode interface. The use of aluminum alloy instead of copper alloy for the main body helps reduce the total weight to approximately 28 oz (790 g), thereby reducing operator fatigue during extended use. The cable connection is designed for heavy-gauge conductors, accepting 3/0 to 4/0 AWG welding cables. The cable is typically secured via a large oval-point screw mechanism or a similar mechanical lug system, ensuring a low-resistance connection that prevents overheating at the handle.

Insulation & Safety:
Thermal and electrical insulation is provided by high-impact, heat-resistant fiberglass compound molded parts. These insulators cover the upper lever and the tip of the jaws, protecting the holder from accidental arcing against the workpiece and shielding the operator from heat. The handle is also molded from durable fiberglass material, designed with ventilation channels in some variations to aid in cooling. The heavy-duty spring is insulated from the current path, preventing annealing and loss of tension over time. The AF-3 is fully repairable, with replacement parts available for the insulators, spring, and hinge pin, making it a cost-effective long-term solution for industrial welding operations.