I looked at that picture inside the chassis, and my first thought was: "Damn, how many times would my head bounce off of the frame before I got it undercontrol when a spark went down the neck of my shirt". Hell of a welder, and great self control.
Doug
TIG welding (more modernly called "GTAW", and formerly referred to as "heliarc") isn't known for making a lot of sparks. If
done right, it provides very delicate, precise control, and I tend to think of the process as "metal surgery". Some other welding
processes that do provide a lot of sparks are generally called "stick welding" or "MIG welding".