That need is what led [Erwin Ried] to purchase a small, battery-powered spot welder from a maker in Korea and test it out on nickel strips. The spot welder [Erwin] used is the work of a user by ...

[marco] sent in this video (scroll down) showing how to make a vacuum tube by hand. The page and captions are in french, but it’s pretty interesting to watch. A small spot welder, some fairly ...