Glassblowing #2: Making a tungsten lamp and (bad) vacuum diode
A detailed account of glassblowing experiments to create a tungsten lamp and a vacuum diode, discussing the techniques, challenges, and imperfect results encountered during the process.
Background
This is a technical blog post about DIY glassblowing and vacuum tube fabrication. The author is attempting to build early-20th-century-style electronic components from scratch: a tungsten-filament incandescent lamp and a crude vacuum diode (a two-electrode tube that allows current to flow in only one direction). The "bad" in the title reflects that the homemade vacuum is imperfect, so the diode doesn't work properly. Key context: vacuum tubes (valves) were the foundation of electronics before transistors; creating a functional one requires both a near-perfect vacuum and pure tungsten wire (which is brittle and hard to work with). The post documents the glassblowing, filament mounting, and evacuation process — a hands-on engineering archaeology project that shows just how difficult early electronics were to manufacture.