“Lichtenberg figure burning” was something I had never heard of until three or four years ago when I saw some viral videos of people using homemade contraptions to make beautiful branching “fractal” patterns that look like a cross between a lightning bolt and a tree.
But before I talk about the Conestoga Works Wood Burner, a professional tool designed to safely create these patterns, here are a few words of warning about some of the homemade machines I've seen. Videos on making your own unit show using transformers that are far too powerful and greatly increase the risk of a fatal accident. If you don't know much about electricity and don’t take steps to avoid electrocution, you don't have any business making your own burner.
The American Association of Woodturners says about 10 people have died from these devices to date, though it suspects the number may be higher. In 2017, the AAW banned all Lichtenberg/fractal burning from its competitions.
If I were to make a list of ways to avoid an accident, it would include at minimum: Avoid being grounded by wearing thick rubber-sole shoes or standing on a rubber mat. Use a GFCI outlet or extension cord (like this DeWalt Power Strip). That way, should something happen the circuit will trip. Wear gloves designed for use with high voltage. Do not touch the probes or the material being burned while the unit is on.
Do not let anyone else touch the unit, such as a curious child. Pay attention at all times. Avoid contact with other material and don’t operate it on your tools. Operate it on a nonconductive surface.
Because of the hazards involved with a DIY rig, I opted for a commercially available unit from Conestoga Works. Conestoga Works is a small company based in Edmond, Okla., whose founder, Charles Waggoner, has a background as an electrical engineer. He developed his Lichtenburg Figure Wood Burner with safety in mind. He included features like a foot switch that immediately shuts the unit off when your foot disengages. This is critical, because if you are shocked, you are going to jump immediately.
Additionally, the insulators on the probes are equipped with a collar that should stop your hand from making contact with the tips of the probe should your hand slip. Charles also kept his transformer at 35-mA, which is much safer than the hundreds of mA people are pumping through microwave transformers.The chances of it killing you without an underlying health condition are next to zero. That’s far better odds than with a homemade contraption. Still, the unit is shipped with a list of instructions and safety precautions that should not be ignored. On the company’s website, you will find multiple downloads and publications on the art, safety, and practice of Lichtenberg figure burning as well as the origins of the name “Lichtenberg figures.”
The Wood Burner itself is robust. It’s made in the U.S.A. The housing and foot switch are both steel with little frill or embellishments except for the safety instructions—repeated once again outside the manual for those who don't read manuals. The cables to the probes are heavy gauge and of ample length to allow free movement while avoiding bodily contact with the work. The body of the unit includes a red indicator light letting you know when the unit is on as well as two molded storage cubbies to hold the probes when not in use.
THE MATERIALS
Any wood can be used, but tighter-grained, lighter-colored woods will produce a more dramatic effect given the contrast. Think basswood, birch, cherry, maple. The tight grain will also give the extra-fine hairs an easier path of travel, resulting in a more grandiose pattern. Woods like oak and ash will burn but may lack the fine details found in these other woods, according to Conestoga. Veneer-grade plywood does surprisingly well and I found ¼-inch maple ply made for easy conduction and fine, detailed burns.
THE PROCESS
Lichtenberg figures are achieved by high-voltage electricity traveling through an electrolyte solution that has soaked into the wood grain. This video captures the process in pretty good detail. Conestoga recommends a mixture of two tablespoons of baking soda per quart of water. The mixture is then sprayed on the work. Allow the solution to dry a bit, remove your probes from their holders, press their ends into the work piece, and depress the foot switch.
You can manipulate the pattern by carving a channel with a chisel to a desired shape and filling it with the solution. It’s not foolproof and some figuring will be seen outside the lines, but it’s a neat hack for guiding the figures in a desired direction. From here, the best way to find what works best for you is experimentation. Have fun with it. You can add more or less baking soda to the water or try positioning the probes differently, too.
CONCLUSION
Lichtenberg figure burning can be a safe and fun activity—as well as a cool and affordable addition to your woodworking shop or practice—for even those with no woodworking experience. Following the instructions and observing electrical safety can ensure the experience is pleasant as well as repeatable.
Once again, I highly recommend buying a commercially available unit rather than making your own. I recommend the Conestoga version for its overt attention to safety; for example: “The insulational value of the probes above the washers exceed the operational voltage of the burner by 585% while the cable insulation is providing an insulational value in excess of 400%.” And the owner’s willingness to walk you through the process to ensure you are safe and enjoying the units he builds is great.
If you are interested in learning more on the process and perhaps speaking to the inventor of this unit, visit Conestoga and check out the downloadable PDF files full of great info and project galleries.
$299 – ConestogaWorks.com
