200 AC/DC TIG problems

I have a new Eastwood 200 AC/DC TIG welder. I am getting welds that are slightly rough and dark grey. I am welding steel tubing with ER70S-2. Various argon flows 12-20, 3/32 red code tungsten, 40-110 amps. Using the foot pedal.

I have left the argon on via foot pedal to clear the hose of air. I have varied the tungsten end shape and made certain not contaminated. The steel tubing was abraded on a belt sander with new belt, as was the tungsten.

Several decades ago I spent years fabricating race car parts with TIG, so I am familiar with it.

At this point it seems to be a failure to envelope the puddle with argon so that it oxidizes. It is not so bad as to be no argon at all.

I just remembered further. The very first bead of the machine, when other things were wrong, I smelled a familiar odor which I always associated with TIG welding, and presumed to come from the arc in an argon atmosphere. Haven’t smelled that since.