The Hacksmith: Retractable Plasma Lightsaber

By The Hacksmith

This project was created by Engineering Superheroes of Hackmith Industries.


Over the past four years, Hacksmith Industries has been working to improve its lightsaber designs. The team began their lightsaber journey with a Tungsten rod heated by a battery pack, later shifting to more stable rod materials to prevent potential hazards at their workshop. Each version of the lightsaber has been more durable than the last, but they still weren’t considered authentic lightsabers because they couldn’t retract, and their blades were solid.

For The Hacksmith’s sixth version of the lightsaber project, the team went in a different direction. Instead of an even more stable lightsaber with a metal rod, the team opted to create the first real, retractable plasma lightsaber. See how it was made in the video below!


Catching Up With The Lightsaber Projects

As mentioned above, Hacksmith Industries has five earlier lightsaber designs, all of which can be found on Check them out at the links below to see the evolution of The Hacksmith’s lightsaber technology!

How Does it Work?

The primary challenge in designing a lightsaber comes from controlling the plasma beam so it stays in place and creates a blade. Electromagnets can guide plasma, but that would mean the lightsaber must remain inside something. Because lightsabers are meant to be handled and used to chop stuff up, this wouldn’t work.

The key to guiding the plasma beam in this lightsaber is laminar flow, a fluid dynamics concept where flowing liquids maintain a near-constant shape even though they aren’t driven by something like a pipe. The most common examples are waterfalls maintaining their shape and water flowing in a steady stream from a hose’s end.

With a solution for guiding the plasma, there were still complexities in powering the beam. Previous lightsaber designs used LiPo batteries, but an actual beam of plasma would require more energy-dense fuel. The team would need to move away from batteries to make this possible. Liquid propane gas provides almost 50 times more energy per kilogram than a LiPo battery. Oxygen is added to the propane from another tank to give the lightsaber even more power and achieve full combustion.

Liquid propane gas compared to LiPo batteries

A screengrab from The Hacksmith lightsaber video comparing liquid propane gas to LiPo batteries.

Due to the lightsaber’s high temperature, a quality nozzle must be used to channel all of this power. This particular lightsaber utilized a nozzle for glass blowing. Previous lightsaber designs reached temperatures of about 2500°F, and the plasma lightsaber reaches up to 4000°F.

Different chemicals can be added to the plasma beam to make it glow in different colors with Jedi shades like green, blue, and yellow and Sith shades like red and orange (no purple yet, sorry Mace Windu).

The final step in creating this lightsaber was adding a circuit to the hilt, giving the user the ability to turn the blade on and off for retractability. And, of course, a sound module was incorporated for the lightsaber noises. With everything assembled, The Hacksmith has now created the world’s first real plasma lightsaber!

Schematic and BOM