Spot welding excessive current test

Brief callback to the prior session's story about pushing spot welding to ~2000 A — at which point the J² scaling of the plasma jet force makes the molten metal spray uncontrollably, the same physics that limits GTA above ~200 A to "humped bead" defects.

I told you the story on Friday of the spot welding where they tried to go to 2,000 amps. If I square 2,000 as opposed to squaring 200, I get tremendous jet pressures, and it just sprayed molten metal all over the room. It's a great cutting action. In fact we actually do carbon arc gouging, where we take a tungsten or hollow carbon electrode and blow compressed air through it and strike an arc. We melt the material and use compressed air to blow it away. You can do that with a regular arc — it's just at 2,000 amps you can't control it very well, it'll just go everywhere.