How Are Neon Signs Made?
From Glass Tubes to Glowing Art
Neon signs have been lighting up streets, shop windows, and art galleries for over a century. Their bright colors and vintage charm make them timeless, but have you ever wondered exactly how they’re made? Creating a neon sign is both a science and an art, requiring skilled craftsmanship and precise materials.
In this article, we’ll take you step-by-step through the fascinating process.
1. Designing the Sign
The process starts with a design—either a text logo, shape, or custom artwork. Designers use specialized software to create a template, which will later guide the bending of the glass tubes. The layout must consider letter spacing, curves, and how the tubes will be connected for an even glow.
2. Selecting and Preparing Glass Tubes
Neon signs are made from hollow glass tubes, usually ranging from 8 to 15 mm in diameter. The glass comes in clear, frosted, or colored forms, depending on the desired effect.
Before bending, the tubes are cleaned to remove any dust or impurities, ensuring that the gas inside remains pure for optimal brightness.
3. Heating and Bending the Glass
This is where the real craftsmanship begins. Using a gas burner or ribbon burner, artisans heat specific sections of the tube until the glass becomes soft and pliable. While the glass is still hot, they carefully bend it along the template, often using blow hoses to prevent collapse and keep the tube’s diameter consistent.
This step requires years of experience—overheating can cause the glass to bubble or break, while underheating will make it too stiff to bend properly.
4. Adding Electrodes
Once the tubes are shaped, metal electrodes are fused to each end. These are essential for conducting electricity into the gas. The connection must be airtight to prevent leaks.
5. Removing Impurities (Bombarding)
Before filling the tubes with gas, the inside must be thoroughly cleaned through a process called bombarding. A high-voltage current heats the glass and electrodes to burn off any impurities or moisture. This step is crucial—contaminants can reduce brightness and shorten the life of the sign.
6. Filling with Gas
The type of gas determines the color:
Neon gas → bright red-orange glow
Argon gas with mercury → blue light (phosphor coatings inside the glass can create other colors)
The gas is pumped into the tube under low pressure, then sealed.
7. Sealing and Testing
Once filled, the tube is sealed completely and connected to a power source for testing. If the tube lights up evenly without flickering, it’s ready to be assembled into the final sign.
8. Mounting and Wiring
The finished tubes are mounted onto a backing—acrylic, metal, or another frame—using clear clips. Wires are connected to a transformer that regulates the voltage and ensures safe operation.
Conclusion
The making of a neon sign combines art, chemistry, and craftsmanship. Each piece is handcrafted, meaning no two signs are exactly alike. From bending delicate glass to filling it with luminous gases, every step contributes to that warm, nostalgic glow we all know and love.
