OPERATION
3) After the settings, press L Knob and R Knob for confirmation;
§4.1.4 Wire Feed Roller Selection
The importance of smooth consistent wire feeding during MIG welding cannot be emphasized
enough. Simply put the smoother the wire feed then the better the welding will be.
Feed rollers or drive rollers are used to feed the wire mechanically along the length of the welding
gun. Feed rollers are designed to be used for certain types of welding wire and they have different
types of grooves machined in them to accommodate the different types of wire. The wire is held in
the groove by the top roller of the wire drive unit and is referred to as the pressure roller, pressure is
applied by a tension arm that can be adjusted to increase or decrease the pressure as required. The
type of wire will determine how much pressure can be applied and what type of drive roller is best
suited to obtain optimum wire feed.
Solid Hard Wire - like Steel, Stainless Steel require a drive roller with a V shape groove for optimum
grip and drive capability. Solid wires can have more tension applied to the wire from the top pressure
roller that holds the wire in the groove and the V shape groove is more suited for this. Solid wires
are more forgiving to feed due to their higher cross sectional column strength, they are stiffer and
don’t bend so easy.
Soft Wire - like Aluminium requires a U shape groove. Aluminium wire has a lot less column
strength, can bend easily and is therefore more difficult to feed. Soft wires can easily buckle at the
wire feeder where the wire is fed into inlet guide tube of the torch. The U-shaped roller offers more
surface area grip and traction to help feed the softer wire. Softer wires also require less tension from
the top pressure roller to avoid deforming the shape of the wire, too much tension will push the wire
out of shape and cause it to catch in the contact tip.
Flux Core / Gasless Wire - these wires are made up of a thin metal sheath that has fluxig and metal
compounds layered onto it and then rolled into a cylinder to form the finished wire. The wire cannot
take too much pressure from the top roller as it can be crushed and deformed if too much pressure is
applied. A knurled drive roller has been developed and it has small serrations in the groove, the
serrations grip the wire and assist to drive it without too much pressure from the top roller. The down
side to the knurled wire feed roller on flux cored wire is it will slowly over time bit by bit eat away
at the surface of the welding wire, and these small pieces will eventually go down into the liner. This
will cause clogging in the liner and added friction that will lead to welding wire feed problems. A U
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