Got some empty plastic bottles in your recycling bin or cluttering up your desk? Then you’ve got a large portion of the material you need for building your own Wimshurst machine like [Thomas Kim] did. This demonstration and build video is one of the many treasures of his YouTube channel. He shows the machine in operation and then spends several real-time minutes showing how he made the heart of it using plastic bottles, the conductive brush from a laser printer, discarded CDs, and a bunch of copper wire. As a bonus, he removes the conductive material and paint from a CD with a homemade taser. As a super special bonus, there’s no EDM soundtrack to this video, just the sounds of productivity.
The Wimshurst machine is an electrostatic generator that slightly predates the Tesla coil. It works by passing a charge from one spinning disk to another disk spinning in the opposite direction. When the charge reaches the collecting comb, it is stored in Leyden jars. Finally, it gets discharged in a pretty spark and the cycle begins anew. Once you’re over shocking your friends, use your Wimshurst machine to make an electrostatic precipitator.
Until recently, watches have been entirely mechanical where each wheel, gear, and mechanism representing a milestone in our understanding of precision manufacturing and timekeeping.
Today it is nearly impossible to find watchmakers to service or repair vintage mechanical pocket and wristwatches, so we have to do it ourselves. Learn to repair vintage mechanical watches. You can do this and we’ll show you how.
GoPro cameras come out of the box with a huge set of features. Most people will be satisfied, or possibly even overwhelmed by the available options, but if you’re able to do some of these hacks, you’ll be able to expand your camera’s capabilities even more. They can, however, void your warranty, so as with most hacking, do these at your own risk.
Finally somebody has found a good use for all those old CRT computer monitors finding their way to the landfills. [Steven Dufresne] from Rimstar.org steps us through a very simple conversion of a CRT computer monitor into a high-voltage power supply. Sure you can make a few small sparks but this conversion is also useful for many science projects. [Steve] uses the monitor power supply to demonstrate powering an ionocraft in his video, a classic science experiment using high voltage.
The conversion is just as simple as you would think. You need to safely discharge the TV tube, cut the cup off the high voltage anode cable and reroute it to a mounting bracket outside the monitor. The system needs to be earth grounded so [Steve] connects up a couple of ground cables. One ground cable for the project and one for a safety discharge rod. It’s really that simple and once wired up to a science project you have 25kV volts at your disposal by simply turning on the monitor. You don’t want to produce a lot of large sparks with this conversion because it will destroy the parts inside the monitor. The 240K Ohm 2 watt resistor [Steve] added will help keep those discharges to a minimum and protect the monitor from being destroyed.
Yes this is dangerous but when you’re working with high-voltage science experiments danger is something you deal with correctly. This isn’t the safest way to get high-voltage but if you have to hack something together for a project this will get you there and [Steve] is quite cautious including warning people of the dangers and how to safely discharge your experiment and the power supply after every use. This isn’t the first high-voltage power supply that [Steve] has constructed; we featured his home-built 30kV power supply in the past, which is a more conventional way to build a HV power supply using a doubler or tripler circuit. Join us after the break to watch the video.
Calligraphy is a rewarding hobby that is fairly inexpensive to get in to. For someone just starting out, poster nibs are a great way to practice making letterforms without worrying about applying the proper pressure required to use nibs that split. With a few tools, you can even make your own poster nibs like [advicevice] does in this Instructable.
Poster nibs are typically made with a single piece of brass that’s folded at the point where the nib touches the paper. The backside forms a reservoir that holds the ink. The other end is formed into a semicircular shank that is inserted into a nib holder. The nibs that [advicevice] made consist of two pieces of flat brass stock plus a section of brass tubing for the shank of the nib. One side of the nib is slightly thinner than the other to act as a reservoir. This keeps ink clinging to the nib through the magic of surface tension.
Nib construction is fairly simple. [advicevice] cut the brass stock to the desired length and width, cut notches with a jeweler’s saw to allow the ink to flow, and cut a piece of tubing that holds the nib snugly. He recommends using three grades of sandpaper on the edges of the brass stock and tubing. After soldering the nib to the shank, he beveled the business end by rubbing it on 150-grit sandpaper. He followed this with 350- and 600-grit papers to avoid injury and tearing the paper when writing.
This is a great example of using a thermoelectric generator for a project. [Joohansson] made both a functional, and aesthetically beautiful fan using components from a computer.
Thermoelectric generators (TEGs for high temperatures, and cheaper TECs for lower temperatures) are also called peltier elements, which look like small square pieces of ceramic with two wires sticking out of them. If you supply power to it, one side will become hot, and the other cold. The TECs [Joohansson] is using want a temperature difference of 68C between either sides. They are typically used for cooling electronics and even some of those cheap mini-fridges will make use of one with a giant heat sink on the hot side.
In addition, they can be used as an electric generator, thanks to the seebeck effect. If you can create a temperature differential between the two sides, you can generate electricity. Using a CPU heatsink, cooler, and fan, [Joohansson] was able to power a small DC fan using only a candle. It’s a brilliant demonstration of the seebeck effect.
Professional photography lighting can be expensive. Sometimes the professional photographer may not want (or need) to spend the big bucks on lighting. [Alex] is one of those folks. He needed a specialized light source and instead of going out and buying some, he made exactly what he needed out of components unlikely to be found in a photography studio.
The project started off with some off the shelf $12 Home Depot under-cabinet lights. Foam core board was attached to the sides of each light to adjust the beam’s width. Opening and closing these foam flaps allow the light beam to be adjusted to ensure the perfect shot. The entire assembly was then taped to long, thin pieces of wood. The wood’s sole purpose is to facilitate mounting of the light.