Introduction: Settings on the MIG Welder

MIG stands for Metal Inert Gas.

MIG Basics

The basic steps to MIG weld:

  1. The material must be grounded to the welder with the ground clamp.
    • Connect the ground clamp close to the area to be welded.
    • Grind any rust or paint before attaching the ground clamp.
  2. When the trigger is pulled, the welder electrically energizes a wire on a spool inside the welder.
    • The wire is pushed through the hose, and out the end of the torch.
  3. A shielding gas flows from a compressed gas cylinder to the end of the torch.
    • The gas keeps oxygen away from the weld until it cools and solidifies.
  4. An electrical arc forms between the wire and the workpiece, creating temperatures high enough to melt the wire and workpiece.
  5. The workpieces and wire melt and flow together, creating a single piece of metal.
    • The resulting weld should be stronger than the original material.

Adjustments and Settings

There are two main adjustments for welding.

  • Voltage
    • Higher voltage creates more heat, which is used for thicker material.
  • Wire speed
    • Faster wire speed will put more wire out the end of the torch. Higher voltage usually requires a higher wire speed.

Always adjust the welder to match the wall chart that shows the suggested settings based on wire size, shielding gas, metal alloy and metal thickness.

Control Panel

The Miller 252 at Pier 9 has a simple control panel, but many other MIG welder control panels will look very similar.

  1. Use the metal thickness and wire feed chart to determine voltage and wire speed.
  2. Set the voltage with the voltage knob.
    • The display will show the voltage.
  3. Set the wire speed with the wire speed knob.
    • The display will show wire speed in inches per second.