Noble! Bright! Antiquated! Neon.
I’m hooked on day-long classes at Oakland’s Crucible. Last Sunday, I spent the day at the Crucible to learn about neon lighting. The Crucible work space is divided into departments. On the second floor in the back hides a neon studio full of gas burners, boxes of glass tubes, and one huge apparatus called the bombardier.
For the class, two guys in their fifties taught eight of us students how neon signs work. Under an electrical current, neon gas glows bright red. Argon gas glows faint blue. Other gasses glow as well, but don’t last as long as these inert two. You can generate a brighter blue color by adding a little mercury vapor to the argon – something not done for this introductory class. Other colors require a tube coated with a phosphor to convert the blue mercury/argon vapor into purples, greens, and yellows. Although pure neon or argon is expensive, very little gas is added to each tube. The cleaner the tube, the longer the neon will last – up to decades.
In my previous welding class, I worked with high-current (A), low-voltage (9-12V) electricity to melt steel. Neon shines with the opposite kind of low-current (mA), high-voltage (kV) electricity. Although neon is rather safe, you can zap yourself if you touch the 2-3 kV electrodes. The higher the voltage, the longer length of neon you can light. A large sign may require 15kV, enough to give you a serious shock. A small transformer box converts the wall’s 120V into the required 2-15kV. Even battery-operated transformers are now available, perfect for a neon project I may want to wear.
Once the glass is shaped, we learned how to cap the ends of the tubes with two wire electrodes. To fill the tube with neon, the instructor at the bombardier apparatus first heats up the tube under vacuum with an electrical current to dry out the glass and remove impurities that would reduce the lifetime of the neon. Finally, he passes a small amount of neon into the tube and then seals the two electrodes.
We spent most of the day cutting, melting, and bending 10mm-think glass tubes. Although phosphor-coated tubes are expensive, simple glass is just seventy-five cents per four-foot section.
The glass melts easily enough at low temperature that neither gloves nor goggles are required, unlike with welding. We stood all afternoon in front of several mounted torches with arcane names like cross-fire, ribbon bender, or five-point. Although the instructors explained how to make switch-backs and 90-degree bends, tube bending is much more an acquired skill. As the hot glass turns into cooked spaghetti, there remain only a few seconds to curl it, while you blow at the same time through a rubber tube into the glass.
Most of the time, my bends unfortunately crimped or elongated. Not much to fix these defects except pick up more glass and try again. By the end of the day, I left exhausted from all the heat, concentration, and glass blowing. Still, I could shape primitive sawtooth shapes, bends, and curls.
We took home a “found object,” a small piece of neon that we are to incorporate over the week into a sculpture. I will add the small circle I received to a reproduction of the Mona Lisa.
I return next Sunday to work on a project of my own devising. At home, I have bent steel wire into three possible forms: a cartoon light bulb filament, a three-dimensional heart, or the silhouette of a dinosaur. On Sunday, I’ll try to bend all three and take home the one sculpture that works out the best. I will fill the winner with neon gas that shall glow bright red.
I would like to mount my little light to illuminate a room, serve as a sign, or put on top of a pole. I worry about the fragility of the glass, but perhaps there is a way to encase the neon tube in a plexiglass box.
Overall, it was quite delightful to immerse into an artisanal industry like neon. Because signs are still made manually and in reduced number, most neon manufacturers are small shops. The two artists who lead the class certainly love the medium and enjoy explaining it to students. They were eager to hear that I’m a physical chemist who may know a little of the psychic behind that unearthly glow.