Star Trek — as much as we love it — was guilty sometimes of a bit of hyperbole and more than its share of inconsistency. In some episodes, ion drives were advanced technology and in others they were obsolete. Make up your mind!
The ESA-JAXA BepiColombo probe is on its way to Mercury riding on four ion thrusters developed by a company called QinetiQ. But unlike the ion drive featured in the infamous “Spock’s Brain” episode, BepiColombo will take over seven years to get to Mercury. That’s because these ion drives are real.
The craft is actually two spacecraft in one with two different Mercury missions. The Mercury planetary orbiter will study the surface while the magnetosphere orbiter will study the little planet’s magnetic field. Check out a video about the mission, below. The second video shows [Neil Wallace] talking about how the ion propulsion — also known as solar electric engines — differ from traditional chemical thrusters.
In his continuing bid to have his YouTube channel demonetized, [Cody] has decided to share how he makes chlorine gas in his lab. Because nothing could go wrong with something that uses five pounds of liquid mercury and electricity to make chlorine, hydrogen, and lye.
We’ll be the first to admit that we don’t fully understand how the Chlorine Machine works. The electrochemistry end of it is pretty straightforward – it uses electrolysis to liberate the chlorine from a brine solution. One side of the electrochemical cell generates chlorine, and one side gives off hydrogen as a byproduct. We even get the purpose of the mercury cathode, which captures the sodium metal as an amalgam. What baffles us is how [Cody] is pumping the five pounds of mercury between the two halves of the cell. Moving such a dense liquid would seem challenging, and after toying with more traditional approaches like a peristaltic pump, [Cody] leveraged the conductivity of mercury to pump it using a couple of neodymium magnets. He doesn’t really explain the idea other than describing it as a “rail-gun for mercury,” but it appears to work well enough to gently circulate the mercury. Check out the video below for the build, which was able to produce enough chlorine to dissolve gold and to bleach cloth.
We need to offer the usual warnings about how playing with corrosive, reactive, and toxic materials is probably not for everyone. His past videos, from turning urine into gunpowder to mining platinum from the side of the road, show that [Cody] is clearly very knowledgeable in the ways of chemistry and that he takes to proper precautions. So if you’ve got a jug of mercury and you want to try this out, just be careful.
If you haven’t heard of it, the Mooshimeter is a two channel multimeter that uses your smartphone as a display over Bluetooth 4.0. The ability to simultaneously monitor voltage and current is rather unique, and the fact that you aren’t physically tethered to the thing makes it ideal for use in hard to reach or even dangerous locations. The promotional material for the Mooshimeter shows users doing things like leaving the device inside the engine compartment of a car while they drive around and take readings about the vehicle’s electrical system.
All that sounds well and good, but at the end of the day, the Mooshimeter is probably not going to be your primary multimeter. It’s going to stay on a shelf until a task befitting its unique abilities comes along. Unfortunately, as [nop head] found, that can be a problem. Like many modern devices, the Mooshimeter doesn’t actually turn off. It just sits there draining its battery until you’re ready to use it. Which of course means that when you’re finally ready to pull the thing out and put it to use, you get a low battery warning and need to put new AAs in it. First World problems.
The fix for this thoroughly modern problem is delightfully old school: a mercury tilt switch.
Using a small spacer made of Kapton tape, [nop head] was able to isolate the battery contacts from the PCB itself. He then soldered the mercury switch in place between them, making sure to position the bulb vertically. When the Mooshimeter is right side up, the mercury flows down and bridges the contacts; but when the device is inverted the contact is broken and the batteries stop draining. He still has to remember to put the Mooshimeter face down when he’s done with it, but it’s better than dealing with constant dead batteries.
Before the Saturn V rocket carried men to the moon, a number of smaller rockets carried men on suborbital and orbital flights around the Earth. These rockets weren’t purpose-built for this task, though. In fact, the first rockets that carried people into outer space were repurposed ballistic missiles, originally designed to carry weapons.
While it might seem like an arduous task to make a ballistic missile safe enough to carry a human, the path from a weapons delivery system to passenger vehicle was remarkably quick. Although there was enough safety engineering and redundancy to disqualify the space program as a hack, it certainly was a clever repurposing of the available technology. Read on for the full story.
Sure, we could just slap the steam-punk label on this doorbell hack, but we think that cheapens it. The rig uses a combination of mercury switch and creative mechanics to form a doorbell. And we think it goes beyond aesthetics to a statement of who you are starting with the front door of your house. No wonder [Nick Normal] has moved it along with him from home to home over the years.
The portion to the right is the ringer itself. Pulling on the lever moves the chain through an eyelet to affect the mercury switch mounted above. That switch completes the circuit which drives the motor on the “bell” unit. We use quotes because instead of ringing a bell it’s striking the large valve control wheel which looks like it came straight from the same industrial plant where The Joker took his unfortunate fall into a vat of acid.
[Glass Giant’s] wrist-mounted fireball launcher adds a little stage magic to his life. This method of fire production is several orders of magnitude less dangerous than other arm-attached flamethrowers or instrument-mounted torches. The module, which is strapped to the underside of his wrist, stores and lights a combination of flash cotton and flash paper. The two flammables are housed in a small aluminum tube touching a glow plug. A slider switch acts as a safety, completing the circuit from the battery, to the glow plug, terminating in a mercury switch which heats things up when held at the proper level. He’s still working out the best way to load the flash materials but as you can see in the video after the break, this is definitely worthy of the Street Fighter reference.
I’m going to break from the typical Hackaday article format for a moment. I’m smitten, captivated by this wondrous new discovery. Forgive my ignorance for having never seen one of these before, I didn’t go to school for electronics. For those, who like myself wondered, what is this beautiful glowing thing, it is a mercury arc valve rectifier.
This is not some chintzy attempt at neo victorian styling (steampunk if you absolutely must), this is an actual piece of electronics used in the field. Widely used to convert alternating current to direct current for railways and street cars, these could actually be found in the wild. There was a time, that opening a door in a power station would have presented you with this fantastic green and purple glowing orb, dripping mercury sparkling inside. If you are anything like me, you would most likely have been frozen in your tracks, convinced you were bearing witness magic.