A method for manufacturing a continuous sucker rod coil, wherein the method includes the step of selecting a plurality of input coils, each input coil having the same uniform hardness, and each input coil having two free ends. The method further includes the step of fusing adjacent free ends of adjacent input coils together to form one continuous length of rod, the fusing creating fused areas and a heat-affected zone at each fused area. The method also includes the step of treating each of the heat-affected zones to alleviate irregularities induced during fusing. Additionally, the method includes the step of winding the continuous length of rod into a finished coil.