Step 10: Some general guidelines on heat settings
3/16 inch rod = 0.187 inch = 190 amps.
5/32 inch rod = 0.155 inch = 150 amps.
1/8 inch rod = 0.125 inch = 125 amps.
3/32 inch rod = 0.094 inch = 90 amps.
5/64 inch rod = 0.078 inch = 75 amps.
1/16 inch rod = 0.062 inch = 60 amps.
My experience indicates that your actual settings would be a little lower than these suggestions. But, it is still a neat correspondence that the rod diameter in thousandths of an inch is very near to the correct amperage setting.
(The photo is from Bing Images.)