Renewable Hydrogen Sucked From Thinish Air

Stored hydrogen is often touted as the ultimate green energy solution, provided the hydrogen is produced from genuinely green power sources. But there are technical problems to be overcome before your average house will be heated with pumped or tank-stored hydrogen. One problem is that the locations that have lots of scope for renewable energy, don’t always have access to plenty of pure water, and for electrolysis you do need both. A team from Melbourne University have come up with a interesting way to produce hydrogen by electrolysis directly from the air.

Redder areas have more water risk and renewable potential

By utilising a novel electrolysis cell with a hygroscopic electrolyte, the so-called direct air electrolysis (DAE) can operate with humidity as low as 4% relative, so perfectly fine even in the most arid areas, after all there may not be clouds but the air still holds a bit of water. This is particularly relevant to regions of the world, such as deserts, where there is simultaneously a high degree of water risk, and plenty of solar potential. Direct electrolysis of saline extracted at coastal areas is one option, but dealing with the liberated chlorine is a big problem.

The new prototype is very simple in construction, with a sponge of melamine or a sintered glass foam soaked in a compatible electrolyte. Potassium Hydroxide (alkaline) was tried as was Potassium Acetate (base) and Sulphuric Acid, but the latter degraded the host material in a short time. Who would have imagined? Anyway, with electrolysis cell design, a key problem is ensuring the separate gasses stay separate, and in this case, are also separate from the air. This was neatly ensured by arranging the electrolyte sponge fully covered both electrodes, so as the hygroscopic material extracted water from the air, the micro-channels in the structure filled up with liquid, with it touching both ends of the cell, forming the circuit and allowing the electrolysis to proceed.

Hydrogen, being very light, would rise upward through holes in the cathode, to be collected and stored. Oxygen simply passed back into the air, after passing though the liquid reservoir at the base. Super simple, and from reading the paper, quite effective too.

You can kind of imagine a future built around this now, where you’re driving your hydrogen fuel cell powered dune buggy around the Sahara one weekend, and you stop at a solar-powered hydrogen fuel station for a top up and a pasty. Ok, possibly not that last bit.

The promised hydrogen economy may be inching closer. We covered using aluminium nanoparticles to rip hydrogen out of water. But once you have the gas, you need to store and handle it. Toyota might have a plan for that. Then perhaps handling gas directly at all isn’t a great idea, and maybe the future is paste?

Thanks to [MmmDee] for the tip!

Brass Plaque Honors Brother

Brass plaques are eye-catching because no one makes them on a whim. They are more costly than wood or plastic, and processing them is proportionally difficult. [Becky Stern] picked the medium to honor her brother, who enjoyed coffee, motorcycles, and making things by hand. She made some playing card-sized pieces to adorn his favorite brand of hot bean juice and a large one to hang at his memorial site.

The primary components are a vertical salt water bath, DC power supply, metal to etch, scrap steel approximately the same size, and a water agitator, which in this case is an air pump and diffuser stone. You could stir manually for two hours and binge your shows but trust us and take the easy route. The video doesn’t explicitly call for flexible wires, but [Becky] wisely selected some high-strand hook-up leads, which will cause fewer headaches as stiff copper has a mind of its own, and you don’t want the two sides colliding.

There are a couple of ways to transfer an insulating mask to metal, and we see the ole’ magazine paper method fail in the video, but cutting vinyl works a treat. You may prefer lasers or resin printers, and that’s all right too. Once your mask is sorted, connect the positive lead to the brass and the negative to your steel. Now, it’s into the agitated salt water bath, apply direct current, and allow electricity to immortalize your design.

Continue reading “Brass Plaque Honors Brother”

This Motorcycle Uses Water!

Doing the rounds among motorcycle enthusiasts for the last week has been a slightly unusual machine variously portrayed as running on water or sea water. This sounds like the stuff of the so-called “Free energy” fringe and definitely not the normal Hackaday fare, but it comes alongside pictures of a smiling teenager and what looks enough like a real motorcycle to have something behind it. So what’s going on? The answer is that it’s the student project of an Argentinian teenager [Santiago Herrera], and while it’s stretching it a bit to say it runs on sea water he’s certainly made a conventional motorcycle run on the oxygen-hydrogen mix produced from the electrolysis of water. The TikTok videos are in Spanish, but even for non-speakers it should be pretty clear what’s going on.

It’s obvious that the bike is more of a student demonstrator than a road machine, as we’re not so sure a glass jar is the safest of receptacles. But the interesting part for us lies not in the electrolysis but in the engine. it appears to be a fairly standard looking motorcycle engine, a typical small horizontal single. It’s running on a stoichiometric mix of oxygen and hydrogen, something that packs plenty of punch over a similar mix using air rather than oxygen. It would be fascinating to know the effect of this mixture on an engine designed for regular gasoline, for example does it achieve complete combustion, does it burn hotter than normal fuel, and does it put more stress on the engine parts?

You can see something of the bike in the video below the break, and there are a few more videos in his TikTok account. Meanwhile this isn’t the first teenage motorcycle project we’ve featured.

Continue reading “This Motorcycle Uses Water!”

Building A Lightsaber And Scoring A World Record, Too

As we all know, the lightsaber is an elegant weapon, for a more civilized age. [Alex Burkan] is doing what he can to bring that technology to fruition, and even secured a Guinness World Record in the process.

Melty melty.

The build relies on an electrolyzer, splitting water into hydrogen and oxygen gas which is stored in a small tank. This gas can then be released and combusted in a burning stream, creating a weapon with a vague resemblance to a movie-spec lightsaber. With the hydrogen torch burning at temperatures of thousands of degrees, it’s hot enough to melt steel just like in the films.

While the concept of operation is simple, actually building such a device in a handheld size is incredibly difficult. [Alex] highlights key features such as the flashback arrestor that stops the gas tank exploding, and the output nozzle that was carefully designed to produce a surprisingly long and stable flame.

The resulting device only burns for 30 seconds, so you’ve only got a short period of time to do what you need to do. However, unlike previous designs we’ve seen, it doesn’t use any external gas bottles and is entirely self-contained, marking an important step forward in this technology. Video after the break.

Continue reading “Building A Lightsaber And Scoring A World Record, Too”

3D-Printed Tooling Enables DIY Electrochemical Machining

When it comes to turning a raw block of metal into a useful part, most processes are pretty dramatic. Sharp and tough tools are slammed into raw stock to remove tiny bits at a time, releasing the part trapped within. It doesn’t always have to be quite so violent though, as these experiments in electrochemical machining suggest.

Electrochemical machining, or ECM, is not to be confused with electrical discharge machining, or EDM. While similar, ECM is a much tamer process. Where EDM relies on a powerful electric arc between the tool and the work to erode material in a dielectric fluid, ECM is much more like electrolysis in reverse. In ECM, a workpiece and custom tool are placed in an electrolyte bath and wired to a power source; the workpiece is the anode while the tool is the cathode, and the flow of charged electrolyte through the tool ionizes the workpiece, slowly eroding it.

The trick — and expense — of ECM is generally in making the tooling, which can be extremely complicated. For his experiments, [Amos] took the shortcut of 3D-printing his tool — he chose [Suzanne] the Blender monkey — and then copper plating it, to make it conductive. Attached to the remains of a RepRap for Z-axis control and kitted out with tanks and pumps to keep the electrolyte flowing, the rig worked surprisingly well, leaving a recognizably simian faceprint on a block of steel.

[Amos] admits the setup is far from optimized; the loop controlling the distance between workpiece and tool isn’t closed yet, for instance. Still, for initial experiments, the results are very encouraging, and we like the idea of 3D-printing tools for this process. Given his previous success straightening his own teeth or 3D-printing glass, we expect he’ll get this fully sorted soon enough.

DIY Electrolysis Tank: Removing Rust While You Sleep

Anyone who’s done a bit of metalworking will know how quickly your stockpile will pick up a coating of rust with even just a bit of humidity. While welding requires only a bit of wire brushing at the joint areas, cleaning a large frame for paint is a completely different story. The projects [Make it Extreme] gets himself into tend to involve a lot of steel, so he built his own electrolysis tank for rust removal.

Electrolytic rust removal involves placing the piece of steel to be cleaned into an alkaline electrolyte solution (water and washing soda) with a sacrificial steel anode and connecting a low voltage DC supply over the two pieces. [Make it Extreme] started with an old plastic container, around which he built a very neat trolley frame. He obviously put some thought into how the tank will be cleaned, since it can be removed by unscrewing six bolts and removing the top part of the frame.

The high current, low voltage power supply that is required for the process was built using an old microwave transformer. The secondary coil is removed and replaced with coil of thick insulated wire, to convert it into a step down transformer. After the rewinding the transformer outputs about 13 VAC, which is then run through beefy bridge rectifier modules to get a DC current. A custom machined copper bolt terminal is mounted through the side of the tank to attach the sacrificial anode plate to the positive lead of the power supply, while the negative lead is clamped to the rusty steel to be cleaned.

[Make it Extreme]’s projects never get old, with everything from rideable tank tracks to rotary electric guns. Check out the video after the break to see the build and an impressive demo. Continue reading “DIY Electrolysis Tank: Removing Rust While You Sleep”

Extreme Refurbishing: Amiga Edition

The last Amiga personal computer rolled off the assembly line in 1996, well over 20 years ago. Of course, they had their real heyday in the late 80s, so obviously if you have any around now they’ll be in need of a little bit of attention. [Drygol] recently received what looks like a pallet of old Amiga parts and set about building this special one: The Vampiric Amiga A500.

The foundation of this project was a plain A500 with quite a bit of damage. Corrosion and rust abounded inside the case, as well as at least one animal. To start the refurbishment, the first step was to remove the rust from the case and shields by an electrochemical method. From there, he turned his attention to the motherboard and removed all of the chips and started cleaning. Some of the connectors had to be desoldered and bathed in phosphoric acid to remove rust and corrosion, and once everything was put back together it looks almost brand new.

Of course, some other repairs had to be made to the keyboard and [Drygol] put a unique paint job on the exterior of this build (and gave it a name to match), but it’s a perfect working Amiga with original hardware, ready to go for any retrocomputing enthusiast. He’s no stranger around here, either; he did another extreme restoration of an Atari 800 XL about a year ago.