MIG Tuning IN

     The zone of good short arc conditions is about two volts wide. Whenever an arc voltage-feed rate combination falls inside the operating zone a good short arc condition is obtained.

     One way to get a good (stable) condition is to increase the wire feed speed until the arc begins to "bump" and "stub out" on the workpiece. Then decrease the feed rate slightly until the erratic bumpy action disappears. The frequency ratio will be near the optimum.

     Instead of changing the wire feed speed it is also possible to change the power source output. When the slope is set (fixed at one value), merely decrease the voltage setting until the arc begins to bump and stub out. Then increase the voltage approximately 2 - 3 volts. This method, too, will give a good frequency ratio. A similar effect can be obtained with slope controlled power supplies. When the slope is increased (steeper), the arc will begin to stumble and stub out. Decreasing the slope (flatter) will eliminate the stumbling. Avoid taking out too much slope, otherwise, the spatter percent will increase.

     Most short arc welding is done with a standard MIG welding set up. The wire feed speed (current) is adjusted by means of a separate "knob" on the wire feed speed control box. The arc voltage (length) is set by adjustment of a separate "knob" on the power supply. Welding conditions are redily selected by "tuning in" both of the settings.

     The electrode wire stickout or Contact Tip to Work Distance (CTWD) for Short-Circuit Metal Transfer should be 1/4" - 3/8" and give the sound of frying bacon.