018640 - Miller RFC Foot Control Contact Brush Set (2-Pack)

Restore Precision to Your Welding Control

The Miller 018640 Brush, Contact Elect RFC Foot Controls is a critical replacement component designed to maintain the functionality of your Miller remote foot controls. In TIG welding and other processes requiring precise amperage regulation, the foot pedal acts as the primary interface between the operator and the power source. Inside older style heavy-duty pedals, such as the renowned RFC series, a rheostat mechanism is used to vary the resistance signal sent to the welder. This contact brush is the physical element that slides across the rheostat windings, translating mechanical foot pressure into an electrical signal.

Technical Function and Wear

Over time, the mechanical friction of the brush moving against the wire windings causes wear. This is a natural occurrence in electromechanical devices. As the brush wears down, it may lose consistent contact with the rheostat, leading to interruptions in the control signal. Furthermore, carbon buildup or oxidation can degrade the connection. The Miller 018640 is manufactured to precise OEM specifications to ensure the correct hardness and conductivity. Using a brush that is too hard could damage the expensive rheostat windings, while one that is too soft might wear out prematurely. This genuine Miller part strikes the perfect balance for longevity and performance.

Maintenance for Reliability

Regular maintenance of your welding peripherals is just as important as maintaining the power source itself. A failing contact brush can manifest as "dead spots" in the pedal travel, where the amperage drops out or spikes unexpectedly. By replacing the contact brushes with this 2-pack kit, you can restore the linear, smooth response that Miller equipment is known for. This simple repair can often save the cost of replacing an entire foot control unit, extending the service life of your existing equipment significantly.

Compatibility and Installation

This kit is specifically engineered for Miller RFC style foot controls. The package contains two brushes, allowing you to replace both contacts if your specific unit requires it, or keep a spare for future maintenance. Installation typically involves opening the foot control housing, accessing the rheostat assembly, and swapping out the worn brushes. It is a straightforward procedure that brings immediate results to the welder's control capability.