Welding apparatus and methods

A welding apparatus, comprising:

• a first electrode;
• a second electrode opposite said first electrode, said second electrode being movable toward and away from said first electrode;
• a third electrode;
• a fourth electrode opposite said third electrode, said fourth electrode being movable toward and away from said third electrode;
• a first transformer winding adapted to be coupled to a power source;
• and
• a second transformer winding electromagnetically coupled to said first transformer winding and being center tapped to provide a first output and a second output;
• said first output electrically coupled to said first and second electrodes;
• said second output electrically coupled to said third and fourth electrodes;
• said first transformer winding substantially evenly transferring current to said first and second outputs of said second transformer winding when energized by the power source, such that said first and second electrodes are energized substantially simultaneously with said third and fourth electrodes.

A method of welding two structures, the method comprising:

• energizing a first transformer winding;
• transferring energy from the first transformer winding to second and third transformer windings electromagnetically coupled to the first transformer winding;
• energizing first and second opposing electrodes using the second transformer winding;
• and
• energizing third and fourth opposing electrodes substantially simultaneously with the first and second electrodes using the third transformer winding.