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.
[toymotorhead] pieced together this USB controlled power strip to help with his electrical bill. His goal was to be able to have devices turned off automatically when he shut down his computer as well as powered on when he turned his computer on. Another requirement was that the USB be isolated to protect the motherboard from spikes.
The cost of the parts in total were less than $30, and consisted of a solid state relay, some fuses, and some transient voltage surge suppressing diodes. The unit only switches power off or on depending on whether or not the computer is powered up, it doesn’t control the outlets via software. He goes pretty in depth as to how everything works as well as showing nice diagrams and pictures. This should be a fairly quick and simple project, as long as you take the proper precautions for working with high voltage.
[Paul Anderson] sent in this classic quarter shrinker after seeing the can crusher the other day. It’s another high powered pulse shot into a coil system, but uses a solenoid actuated spark gap switch to swith those sweet high voltages. The results are quite impressive.