Wood burning, which goes by pyrography when it’s feeling fancy, has been an art form for centuries. [PapaJ06] puts a new twist on it by using a microwave oven transformer to generate fractal patterns in wood. We’ve seen these Lichtenberg figures before, but generally as electric discharges in acrylic sheets or crystal balls using multi-mega-electron volt accelerators. [PapaJ06]’s technique is considerably simpler and well within the reach of most would-be fractal artists, relying as it does on a transformer salvaged from a $20 Craigslist microwave.
But the extra twist that really brings the wow factor to the fractal patterns burned into the wood is the addition of some phosphorescent resin to fill the valleys carved by the electric discharge. [PapaJ06] carefully prepares the wood, fills the burns with glow powder mixed with epoxy resin, and finishes with a little sanding, linseed oil and polyurethane. The contrast between the charred and intact wood, and the way the resin fills the voids really brings out the fractal nature of the Lichtenberg figures.
[PapaJ06] doesn’t really show us too much about his process, but luckily [TheBackyardScientist] recently posted a video of his process for riding the lightning. Check it out after the break.
https://www.youtube.com/watch?v=BuG1oNRQnyI
[via reddit]
I’m curious about the large piece in the imgur gallery… in the video it looks like the burning stops when the two sides meet so how are multiple designs burned into the same piece of wood?
I did this the other weekend. You can just move the electrodes and start over. However, if the new pattern meets up with an old one the electricity will flow through the charred wood preferentially.
in the video you can faintly make out some alligator clips that he seems to be using to apply power. I imagine the large one was just done multiple times in different locations.
The 8 bit background music (at the end) made me think……this must have been how they procedurally rendered trees in games.
It’s a reasonable guess, but nope. Attempting to model physical processes like this in software would take a huge amount of CPU power. Even if it were not for that, not every pyrographically-modelled “tree” would end up looking like a respectable tree; there’s far too much unpredictability.
What’s often used is an “iterated function system”, abbreviated as IFS. It’s a simple type of fractal. Wikipedia has an article on it. A Google Image search on “IFS trees” or “fractal trees” will show some good examples of the output. There are likely some freeware programs that will let you easily play with them, but as it’s been decades since I’ve used one, I can’t make a current recommendation.
Do you brush out the loose char before adding the resin?
A bit irresponsible not to point out the dangers – a microwave transformer can easily KILL YOU
I have to agree here.
Often I (as a non-American) get frustrated by all the comments about how dangerous just about everything is and that unless you have a friggin full-body armour you can’t use a cordless drill or something, but playing with a MOT should always be done with caution since it can easily put a unhealthy jolt through your heart with bad consequences as a result…
Places like youtube, hackaday, instructables etc have no “minimum skill level” required to view so please put a brief description when something is dangerous, and also perhaps why, so that whoever want’s to have a go at least knows what’s at stake.
To be fair I think everyone knows wood is a terribe condctor of electricity and if you are managing to do this to it, Then you are using something pretty dangerous. I don’t think we will be gettin many people licking the elecrodes to see if it makes your tongue feel funny.
I think you underestimate people’s ability to do stupid things… The fail videos will literally be smokin’
well aren’t you an eletrical genius
a fire extinguisher would be a good idea too in case of fire
microwave ovens can also be picked up for free because people throw out them since they are so cheap.
good sources are.
1. garbage and dumpsters many people even set junkers out by the curb (check with local laws because there may be contracts to require the recycling of appliances).
2. students if you live in a college town there is student housing and they throw out appliances without much regard for recycling laws when they leave for the summer and christmas break)
3. appliance stores and repair shops especially the small mom and pop shops and they maybe even willing to give you just the transformer or discharge or remove the high voltage capacitor for extra safety.
4. recycling centers they can be sketchy since appliances and electronics can be treated the same.
have to agree with mike, MOT, water no warning about how dangerous MOTs are. any idiot could try this and kill themselves quite easily. you dont get5 a second chance at this power level.
I just watched v2 of the Backyard Scientist’s video and have seen that explicit, graphic, and multiple safety warnings don’t do any good because the comments are still dominated by the safety nannies.
Pretty cool artwork, but I think I enjoy watching the process even more.
It’s amazing how people think warnings will stop people doing dumb stuff, its like laws/locks only protecting you from non criminals. If high voltage and big red letters of danger and wood catching fire doesn’t stop you doing something dumb, what will ?
Warning dropping a MOT on someones head is very dangerous and might kill them. Please do not throw microwave ovens at small children. Pets put inside microwave ovens then subjected to high power microwaving for 5 minutes may expire.
Anyway, pretty neat project I do like watching the patterns form in the wood and interesting to see the pathways chosen, i guess some people just want to watch the wood burn.
These are not fractals.
Regarding danger. It’s OBVIOUSLY dangerous, so just telling people that it’s dangerous is pointless. Instead of just repeatedly pointing out the obvious, why not give some useful and specific recommendations for doing it more safely? Here’s a couple:
1) The large HV capacitor in a microwave oven has a bleeder resistor, that drains the charge on the capacitor when the power is off. It’s rare, but it can fail. In which case the capacitor may hold a lethal charge, possibly even for days or weeks. Always consider it failed, and short that capacitor to eliminate the charge prior to ripping out the MOT. I have done it by bridging the capacitor contacts with needlenose pliers, with an insulated grip, while wearing a long rubber glove. Avoid touching the microwave case while doing this. Avoiding touching anything grounded too. You might not be aware of what’s grounded (a drywall corner surprised me with a nasty shock once, I didn’t even know there was metal in them), so basically touch nothing else; and wear rubber-soled shoes to provide some additional insulation from anything in the floor. If the capacitor was holding a charge, there will be a loud bang. Your pliers will have a nice scar on them, and might be spot welded to the capacitor contacts. Better them than you!
2) No common wire has insulation sufficient to reliably hold back high voltage. Not even the most heavily insulated wire you can find at the hardware or automotive store. Don’t touch any part of a high voltage circuit when it’s powered, even an insulated wire. Even if it’s a wire with insulation made specifically for HV, energy can still transfer through that insulation to you capacitively; just like energy transfers to you through the glass of a plasma globe. In a darkened room, you might even be able to see it as a faint blue glow surrounding where you’re holding the wire, with more energetic streams where specks of dust focus the current. Sounds pretty cool, but seriously, don’t try that. It’s enough charge you up to the point where you’ll receive a shock should you touch something grounded (like the aforementioned drywall corner, I’m speaking from direct experience). And while that shock in itself probably won’t be lethal, it WILL make you jerk in surprise; at which point you might touch something far more dangerous, that you would never intentionally touch.
I’ve used a large and long standard screwdriver (with a large resin handle) (with other safety precautions you mentioned), and for shorting big capacitors. As long as you don’t make contact at the very tip, even if the capacitor welds itself to the screwdriver, it can be removed and you still have a functional tool… instead of potentially welding your pliers shut. A nice long screwdriver also can keep your hands (and you) much further away from the voltage (8″+ vs 2″-4″ with the needle nose pliers), greatly reducing the chances of accidentally contacting some part of metal case of the microwave.
Just on more item on the safety side. The insulation on regular thhn wire breaks down at 600 volts. Meaning, the wires on the secondary can shock without touching anything metal. Take a look at a sparkplug cable.
The two links “electric discharges in acrylic sheets” and “crystal balls” seem to go to the same post. I’m pretty sure the second one should be going to a project of mine from a while back ;)
http://hackaday.com/2013/09/16/electron-tree-bridal-gifts/
Thank you and bookmarked! :D
The same sort of features can be seen on a planetary scale as well, especially on Earth and Mars, lending credence to some of the theories proposed under the banner of the “Electric Universe”, which is well worth following up on IMHO if you’re interested in cosmological science.
He uses a croc clip somehow, but I cant see how that sticks in the wood. Maybe he bangs a staple into the wood and clips the croc to that?
I burned my first fractal yesterday with my 12k neon; it went well but took a long time to start burning; I’m experimenting to see if I can get it going faster – any ideas?
I just did my first two Lichtenberg burns today. I am using a 12Kv from a neon sign. All went well but still have a lot to work on. My question to anyone/everyone who has done this already…did you find the baking soda stained the wood? If so, what did you do to clean the wood up? I started to sand mine down but stopped and thought I would ask the question here. I used 2 scraps of 3/4″ B2 Red Oak Wood Veneer Core Plywood I had from a cabinet building project.
Any thoughts? Thank you in advance.
D
Plywood has a little dis-coloration with the soda mix but hardwood reacts badly to a salt treatment I found using lemon juice for hardwood works best
I found that using the soda solution lightly dis-color plywood how ever salty water really effects hardwood so I use lemon juice on hardwoods just have to use a little more of it to work but the results speak for it self
Late post, but diluted Oxalic acid (wood bleach), apply 1 coat, let dry, apply another coat and scrub with nylon brush, let dry, wash off with water and scrub with nylon brush. removes the smell from electrolyte also
Walmart…wood bleach…oxalic acid
Yes wood bleach at paint store
Maybe you’re using too much baking soda; it doesn’t take much.
As for the warnings, let natural selection remove some idiots from our gene pool. Maybe we’ll have a few less democrats.
Stupidity does not hold to party lines.
Does seem to hold to party affiliation though, doesn’t seem to matter what party though, dems, republicans, communist, nazi whatever it is anybody selling himself to a party tends to be an idiot.
Will this work with a car battery and jumper cables? Just curious…
Anybody know if this can be done on sheet metal?
You can’t use this method on sheet metal, your entire work would be electrified as sheet metal is highly conductive. For the appearance you’re wanting on the metal, you’re looking more at Etching.
It’s a totally different process.
about to start burning wood :) and yes safety is my main concern, I’m going to go ahead and make my machine but I’m including a variac unit