Clean the surface of the metal to which you are welding NR 232 wire with a metal brush. Remove surface oils with an industrial degreaser.
Feed the NR232 wire to the torch, inserting it through the guide tube and over the roller. The small hole at the end of the wire liner should be visible; align the NR232 wire with that hole, using a screwdriver. Push the wire into the liner manually, for a few inches.
Switch on the welder. Use the wire feed mechanism to push the wire through the liner. With the tensioner, tighten the tension on the wire until the wire stops slipping.
Consult your manufacturer's instructions to fine-tune both the power settings and the wire speed settings for NR 232 wire. These settings depend on the diameter of the NR 232 wire and on the position at which you are welding. For instance, vertically-welded NR 232 wire that is .068 inches in diameter has an optimal wire feed speed of 110 to 135 inches per minute and voltage of 18-19 V. On the other hand, NR 232 wire, .068 inches in diameter, that is being horizontally welded has an ideal wire feed speed of 168 to 320 inches per minute and voltage of 20-22 V.
Hold the MIG torch with both hands, with the contact tip about 6-10 millimeters from the metal while allowing the wire to touch the metal surface. Fire the torch, following your manufacturer's specific instructions. A zig-zag motion without curves is well suited to thicker wires and metals, while a curving zig-zag motion is better for thinner materials.