You can leave your regulators set for cutting pressures and just 'feather' the valves to get the required flame for your welding tip, but trying to needle down 20 psi of oxygen to 2 psi for a #0 welding tip is touchy at best.
I have a Smith torch set and have a hard time getting consistant pressure regulation below 5 psi. I have heard of dual stage regulators and I suppose that is what I need to properly regulate my pressures, but for now I am getting by.
