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Mig Torch Liners
The liner is both one of the simplest and most important components of a MIG gun. Its sole purpose is to guide the
welding wire from the wire feeder, through the gun cable and up to the contact tip.
Steel Liners
Most MIG gun liners are made from coiled steel wire also known as piano wire, which provides the liner with good
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during operational use. Steel liners are primarily used for feeding of solid steel wires, other wires such as Aluminium,
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and releative to the wire diameter being used and will assit in smooth feeding and prevention of the wire kinking and
birdnesting at the drive rollers. Also bending the cable too tightly during welding increases the friction between the liner
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liner wear and birdnesting. Dust, grime and metal particles can accumalate inside the liner over time and cause friction
and blockages, it is recommended to periodically blow out the liner with compressed air.
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an oversized liner, can cause the wire to wander or drift within the liner. This in turn leads to poor wire feeding and
premature liner failure due to excessive wear. By contrast, larger diameter welding wires, 1.2mm through 2.4mm have
much higher columnar strength but it is important to make sure the liner has enough internal diameter clearance. Most
manufacturers will produce liners sized to match wire diameters and length of welding torch cable and most are colour
coded to suit
Blue - 0.6mm - 0.8mm
Red - 0.9mm - 1.2mm
Yellow - 1.6mm
Green - 2.0mm - 2.4mm
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characteristics and can be used with a variety of wire types such as silicon bronze, stainless steel as well as alumi-
nium. A note of caution to careful inspect the end of the welding wire prior to feeding it down the liner. Sharp edges
and burrs can score the inside of the liner and lead to blockages and accelerated wear.
Polyamide Liners (PA) are made of carbon infused nylon and are ideal for softer aluminum, copper alloy welding wires
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all the way to the feed rollers.
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neck end will increase the working temperature of the liner as well as improve the electrical conductivity of
the welding power transfer to the wire.
Blue - 0.6mm - 0.8mm
Red - 0.9mm - 1.2mm
Yellow - 1.6mm
Black - 1.0mm - 1.6mm
Steel Liners
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PA Liner
Neck Liner
Mig Torch Liner Types
Mig Torch Liner Types
