How to make a neon sign

Real neon signs are made from glass tubing, bent by hand over a flame, filled with neon or argon gas and lit by a high voltage transformer. LED flex and acrylic lookalikes can look similar, but they are a different product made in a different way. This guide is about real glass neon: the craft, the kit and the materials, and where Sign-Tec can help.

Watch it done

These 1980s training films from DACO Neon (the company no longer trades) still show the process well, from bending to bombarding.

Between them they cover the basic bends (including the U bend, drop turn, rise and offset), bending a complete sign to a pattern, then pumping and bombarding on the manifold.

What you need

• Glass tubing: coated (phosphor) or clear, usually 8 to 20mm. See Glostertube coated glass and our neon glass colour chart.
• Electrodes to suit the tube size and current. See Eurolite electrodes and the electrode picker.
• Heat: a ribbon burner, crossfire and hand torch for bending, with gas and oxygen.
• Patterns: a full-size pattern on heat-resistant drawing cloth.
• Processing: a bombarder with a vacuum pump, neon and argon gas and a manifold.
• Finishing: blockout paint, tube supports and silicone caps.
• Power: a SIET transformer or Hansen convertor, with HT cable.

Step 1: Design and pattern

Draw the design full size and reverse it, because tubes are bent face down on the pattern. Plan the sections: where each tube starts and ends, where it goes through the backing and where joins can be hidden. Keeping letters joined cuts down the number of electrodes.

Step 2: Bending

Heat a length of tube evenly until it softens, then bend it to the pattern while blowing gently through a blow hose to keep the bore round. Work one bend at a time, keep the glass turning in the flame so it heats evenly, and check each bend against the pattern before moving on. Bending is a skill that takes practice: start with simple shapes and larger tube.

Step 3: Electrodes

Weld an electrode onto each end of the section. Choose the electrode for the tube diameter and the current the transformer will run. The electrode picker works this out for you.

Step 4: Bombarding and filling

Connect the section to the bombarder (6mm clear tubing is used for the stem that connects it). Pump it down to a vacuum, then pass a high current through the tube to heat the glass and activate the electrodes while the impurities are pumped away. When it has cooled under a good vacuum, fill it with neon for red and orange, or argon with a drop of mercury for blue and most coated colours, and seal it off.

Step 5: Ageing in

Run the tube on a transformer so the gas settles and any faults show up before the sign leaves the workshop.

Step 6: Blockout and mounting

Paint out the parts that shouldn't light, such as returns, joins and crossovers, with blockout paint. Mount the tubes on supports with the electrodes through the backing, fit silicone caps and wire to the transformer with HT cable.

Step 7: Safety and regulations

Signs must be installed to BS 7671 and EN 50107, including protection at touching height and a fire-fighter's switch where the building's fire strategy requires one. See Neon facts for the details.

Learn more

• Neon Techniques: Handbook of Neon Sign and Cold Cathode Lighting (formerly Neon Techniques and Handling), from the Museum of Neon Art shop. The standard reference for the trade.
• Lightwriters Neon Chicago sells The Neon Engineer's Notebook and training DVDs, including Introduction to Neon with Jacob Fishman.
• How to work out tubing, transformers and electrodes, our second tutorial.

Need glass, electrodes or a transformer? Call 01892 783 900 or email enquiries@sign-tec.co.uk. Sign-Tec has supplied the neon trade since 1983.