Circuit to control current, upto 90 amps

[mickeric]

Hi Guys ----This is a bit of a challenge ---sorry!!!

I bought a new combined stick and Tig. welder (thought to be a Chinese clone) I had it for one month. Used it twice and it blew up. I also have a 20 year old 90 amp AC “ buzz box “. The outer case had seen better days, but it is impossible to wear the dam thing out.

To cut my losses I decided to insert the “buzz box” working, into the new case. Adding four 150 amp diodes I converted it, to make it DC. I am really pleased how it welds, stick electrode positive. The output voltage (no load) is 68v I do not know that amperage because I only have a 10 amp multimeter.

The downside of my conversion is that I now can’t control the amperage
My question is ----- does anyone know of a SIMPLE circuit design, to control the amperage.

[winelight]

I would say it would be easier to control the mains input.