Better cover your ass as far as the welding flash goes.
If he claims his eyes are messed up from your welding he will be able to find a lawyer who is more than willing to file frivolous lawsuits.
Do you really want to wager your time, savings and assets on proving him wrong?
The noise? You can setup a webcam and recorder to cover for that.
Flash damage to a person staring at welding flash?
How do you prove that the person didn't suffer damage? He lies - you lose defending yourself.
I will definitely be putting an opaque covering over my welding curtain when I get home. Also, I can listen to my music on headphones, no problem.
As for the noise of metalworking, we will see if he calls solely on that. Maybe I’ll have to permanently close my garage door and put up a soundproof barrier on that entire wall.
Having said that, nobody else has complained about my light or noise. I have two teenagers who work graveyard sleeping in the bedroom adjacent to my shop; they say that they cannot hear me.
Also, my wife runs a daycare in our house, and those kids are sleeping for three hours in the middle of the day; my wife says that she has never heard me the whole time we have lived there. I could go on and on: my mother-in-law lives in a room directly above my shop, and she said she can’t hear me. All of the people that walk by on the sidewalk are very friendly and I very often get a smile and a wave.
I had said that we called the bored & whiny neighbor Baby Chris, but I found out his name is Pat. So we call him Crybaby Pat.
I am out of town for a few months, but my wife says that she sees crybaby Pat come out of his house, look at our house, look up and down the street scrutinizing what is going on, and then walks back in the house a few times a day. He probably misses me because he has nothing to complain about.