How Are Neon Signs Made? Step-by-Step Process From a Neon Expert

Neon signs have been lighting up streets, diners, and bars for over a century. Their glow is instantly recognizable. warm, vibrant, and a little nostalgic. But have you ever wondered how they’re actually made?

As someone who’s spent more than a decade bending glass and filling tubes with gas, I can tell you: neon isn’t just about science, it’s about craft. Each sign is handmade, one tube at a time, using skills passed down through generations.

In this article, I’ll walk you through the materials, the step-by-step process, how the colors come to life, and why neon remains such a unique art form. Even in the age of LEDs.

What Materials Go Into a Neon Sign?

When people see a neon sign glowing on a wall, they often imagine it’s just “gas in a tube.” However, the truth is that every sign is a carefully crafted combination of materials, each chosen for its strength, color, and longevity. After a decade of bending glass and filling tubes, I can tell you. If one part is off, the whole sign fails.

- Glass Tubes:

The backbone of every neon sign. These tubes are usually 8–15 millimeters in diameter, made from soft lead glass, so I can bend them by hand over a flame. The clarity and thickness of the glass directly affect how evenly the light spreads.

- Electrodes:

Fitted at both ends of the tube, these are metal components that allow electricity to flow into the gas. A lot of beginners underestimate electrodes, but they’re the “gatekeepers” of the whole system. Poor-quality electrodes = short lifespan.

- Gases:

This is where the magic happens. Pure neon gas produces that unmistakable fiery red-orange glow. For blues, whites, and other colors, I use argon with a drop of mercury. Over the years, I’ve learned that even the tiniest impurity in the gas can make a sign flicker or fail.

- Coatings & Phosphor Powders:

To expand the color palette, I work with tubes that have special coatings on the inside. These phosphor powders react with the gas and electricity to give off brilliant greens, pinks, and purples. Without coatings, you’d be limited to just neon red and argon blue.

Put these together. Glass, electrodes, gas, and coatings. And you have the building blocks of every neon masterpiece. It looks simple when it’s glowing on the wall, but trust me: every single element has to be perfect before I even think about bending the tube into a shape.

The Step-by-Step Process of Making a Neon Sign

When people ask me how neon signs are made, I always say: it’s equal parts science and patience. I’ve spent years standing over a ribbon burner, sweating over glowing glass tubes, and one thing is certain. There are no shortcuts. Here’s how it’s really done:

1. Design the Sign

Every neon sign starts with a design. Usually, this is drawn on paper or printed on a large pattern sheet. The design acts as a guide for bending the glass tubes into letters, numbers, or shapes.

2. Heat and Bend the Glass Tubes

Long, straight glass tubes are heated over a flame until they become soft and flexible. While hot, the tube is carefully bent to match the design pattern. This step requires precision so the tubes don’t collapse or break.

3. Attach Electrodes

Electrodes are sealed onto both ends of the bent glass tube. These metal parts will later connect the sign to a power source, allowing electricity to pass through the gas.

4. Remove Air and Impurities

The tube is connected to a vacuum pump to remove all the air inside. While under vacuum, the tube is heated to burn off any moisture or impurities. This ensures the gas inside will stay clean and stable.

5. Fill the Tube With Gas

Once the tube is purified, it’s filled with either neon gas (for a red-orange glow) or argon gas with a drop of mercury (for blue and other colors). The tube is then sealed shut.

6. Seal and Test the Tube

The tube is connected to a high-voltage power source. When electricity flows through, the gas inside lights up. At this stage, the sign is tested for brightness, stability, and leaks.

7. Mount the Sign

Finally, the finished neon tubes are mounted onto a backing (like acrylic, metal, or a frame) and wired to a transformer. Once installed, the neon sign is ready to shine.

Every step takes years to master, and that’s why true neon signs are still handmade, one by one. No machine can replicate the balance of heat, timing, and feel that goes into each bend.

How Neon Signs Get Their Colors

Most people are surprised when I tell them this: neon itself only makes one color. red-orange. That’s it. Every other glowing shade you’ve ever seen on a neon sign comes from a mix of gases, coatings, or colored glass. After a decade in the craft, I’ve learned that color-making is where science meets creativity.

The colors of neon signs come from a mix of gases, glass, and special coatings. Here’s the science behind it:

• Neon Gas = Red-Orange Glow

Pure neon gas produces a bright red-orange light when electricity passes through it. This is the “original” neon color and the most intense glow.

• Argon Gas + Mercury = Blue and More

Argon by itself produces a faint lavender glow. When a drop of mercury is added, the interaction creates a strong blue light. From this base, additional colors can be created using coatings.

• Phosphor Coatings Inside the Tube

Some glass tubes are lined with phosphor powder. When the gas inside glows, the phosphor absorbs the ultraviolet (UV) light and re-emits it as visible colors like green, pink, or purple. This is similar to how fluorescent lights work.

• Colored Glass Tubes

Instead of clear glass, manufacturers can use glass that’s already tinted. For example, blue-tinted glass filled with neon gas will give a different shade of blue than clear glass with argon gas.

• Mixing Techniques

By combining gases, coatings, and tinted glass, neon makers can produce more than 150 different colors. That’s why signs can range from classic red to bright greens, purples, and even white tones.

The beauty of neon colors is that they’re not just surface paint. They're alive inside the glass. That’s why neon signs have a glow you can’t fake with LEDs. Each shade is literally born from chemistry and light.

How Long Does It Take to Make a Neon Sign?

The time needed to make a neon sign depends on the size and complexity of the design.

• Small and simple signs (like one word or a short phrase) can take a few hours to one day.
• Medium signs with multiple words, shapes, or color changes usually take two to three days.
• Large or detailed signs with many bends, colors, and custom designs can take a week or more.

Keep in mind that this process isn’t just bending glass. Time is also spent:

• Creating the design pattern.
• Pumping and filling the tubes with gas.
• Testing the sign for leaks and brightness.
• Mounting it securely to a backing and transformer.

In short: the more complex the design, the more time it takes. A simple “OPEN” sign might be finished in a day, while a detailed, multi-color logo could take an entire week.

Common Mistakes Beginners Make While Handmaking a Neon Sign

I’ve trained a few apprentices over the years, and I can tell you. Everyone makes the same mistakes at first. Neon looks simple when it’s glowing on the wall, but when you’re at the torch, the craft is far less forgiving. Here are the pitfalls most beginners run into:

Overheating the Glass

Newcomers often leave the tube in the flame too long. Instead of softening evenly, the glass bubbles or collapses. Once that happens, the tube is useless. You have to start over.

Twisting the Tube While Bending

When you bend glass, you have to keep the tube perfectly flat as it curves. Beginners tend to twist their wrists, which makes the tube spiral. The result? Letters that look sloppy and uneven.

Skipping Proper Pumping

One of the biggest mistakes is rushing the vacuum stage. If the tube isn’t cleaned and purified properly, impurities stay inside. That’s why many first attempts flicker or burn out in days.

Ignoring Electrode Seals

Electrodes look simple, but sealing them perfectly is an art. Beginners often leave micro-gaps where air leaks in, killing the sign before it ever glows properly.

Underestimating Design

Some people jump straight into complex designs before mastering the basics. In reality, even a clean, single-word bend can take hours of practice. Start small. Otherwise, frustration hits fast.

FAQs About How Neon Signs Are Made

Are neon signs made by hand?

Yes. True neon signs are always handmade. Every bend, every seal, every gas fill is done by a skilled artisan. No machine can replicate the precision and touch required to shape hot glass.

Are neon signs actually neon?

Sometimes. Pure neon gas gives that fiery red-orange glow. But other colors come from argon, mercury, phosphor coatings, or colored glass. So while all signs are called “neon,” only the red-orange ones are pure neon gas.

Is neon toxic, yes or no?

No. Neon gas itself is non-toxic and inert. Even if a tube breaks, the gas simply disperses harmlessly into the air. The only caution is with mercury, which is used in some argon-based colors, but it’s sealed inside and handled carefully by professionals.

Are neon signs easy to make?

Not at all. They take years of training and practice to master. While LEDs can be assembled quickly, real neon requires bending glass over fire, sealing electrodes, pumping gas, and testing under high voltage. It’s an art form, not a weekend project.

Does neon ever burn out?

Neon doesn’t “burn out” the way a lightbulb does. The gas can last decades if sealed properly. What usually fails are the electrodes, transformers, or seals. On average, a well-made neon sign will glow strongly for 8–15 years before it needs servicing.

Conclusion

Neon signs may look simple when they’re glowing above a bar or storefront, but behind that glow lies hours of heat, precision, and craftsmanship. From bending fragile glass to sealing in pure gas, every step is a balance of science and artistry.

After more than a decade in this craft, I can tell you. Neon isn’t just light. It’s alive. Each sign carries the handprint of the artisan who shaped it, the chemistry of the gases inside, and the timeless magic that makes neon unlike anything else.

So the next time you see one flicker in the night, you’ll know you’re not just looking at a sign. You’re looking at a piece of living art.