Aleksander Zawada speaks at EHSM.
(Image: Mitch Altman)
In 2006, Aleksander Zawada started a one-man DIY vacuum tube laboratory in Warsaw called "Prywatna Wytwórnia Lamp." Now, with more space, more equipment (mostly from dumpster diving), and the cooperation of his friends, he has created something that is similar to a small research institute. Prywatna Wytwórnia Lamp now has a mechanical workshop, an electronics laboratory, and a vacuum laboratory.
Zawada presented on electron beam welding, a technique for joining metals and alloys that was initially used in the manufacturing of nuclear fuel for atomic reactors around 1950. The principle is to melt materials by heating them using a focused high-energy electron beam (usually 6-120 keV). Traditional electron beam welders use a high vacuum and a complex electron gun system that make the process expensive.
He built something else: a small electron beam welder where a vacuum of 0.01-0.05 Torr is enough. This level of vacuum can be achieved using a cheap rotary pump.
This electron beam welder is not as good as traditional ones, due to poor focusing and the lower energy of electrons. Nevertheless, it is possible to weld wires or thin plates of aluminum, copper, nickel, and other materials.