M1421 - Miller M1421 Teflon Neck Liner for .047-.062 Aluminum Wire

Precision Aluminum Wire Feeding

The Miller M1421 Liner is a specialized component designed to facilitate the smooth transfer of aluminum welding wire. Manufactured from high-quality Teflon, this liner significantly reduces the coefficient of friction compared to standard steel liners. This characteristic is critical when working with soft alloys like aluminum (4043 or 5356 series), which are prone to buckling, shaving, and bird-nesting if subjected to drag within the feeding system.

This specific liner features a length of 10 inches, indicating its primary application as a neck liner or jump liner within the MIG gun assembly. It is engineered to bridge the gap in the gun's neck or handle area, ensuring the wire remains supported and protected right up to the contact tip. The liner accommodates wire diameters ranging from .047 inches (3/64") to .062 inches (1/16"), covering the most common sizes used in industrial aluminum fabrication.

Proper maintenance of the wire feeding path is essential for consistent arc stability and weld quality. Over time, liners can become clogged with debris or worn by the abrasive nature of the wire, even with Teflon. Replacing the neck liner with the M1421 ensures that the final stage of wire delivery is unobstructed, maintaining the integrity of the gas shielding and electrical contact.