Abstract: This welding control method and apparatus automatically adjusts the percent heat of a welding machine in response to the duration of the preceding welds. The duration of each weld is measured by counting the line cycles. The line cycle count is compared with a percent heat increase condition and with a percent heat decrease condition of a preselected percent heat algorithm. The percent heat is incremented in response to the percent heat increase condition being met and the percent heat is decremented in response to the percent heat decrease condition being met. The control detects the weld resistance at the peak of each line cycle and compares the detected resistance with a resistance condition of a preselected resistance algorithm. The weld is terminated in response to the resistance condition being met and the cycle count being between a low limit count and a high limit count.