chemistry hacks

641 Articles

Dark lab setup with scientific looking drink dispenser

Scared For A Drink?

October 31, 2025 by 1 Comment

Halloween is about tricks and treats, but who wouldn’t fancy a bit to drink with that? [John Sutley] decided to complete his Halloween party with a drink dispenser looking as though it was dumped by a backstreet laboratory. It’s not only an impressive looking separating funnel, it even runs on an Arduino. The setup combines lab glassware, servo motors, and an industrial control panel straight from a process plant.

The power management appeared the most challenging part. The three servos drew more current than one Arduino could handle. [John] overcame voltage sag, brownouts, and ghostly resets. A healthy 1000 µF capacitor across the 5-volt rail fixed it. With a bit of PWM control and some C++, [John] managed to finish up his interactive bar system where guests could seal their own doom by pressing simple buttons.

This combines the thrill of Halloween with ‘the ghost in the machine’. Going past the question whether you should ever drink from a test tube – what color would you pick? Lingonberry juice or aqua regia, who could tell? From this video, we wouldn’t trust the bartender on it – but build it yourself and see what it brings you!

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Mushrooms As Computer Memory

October 28, 2025 by 35 Comments

Fungi make up a massive, interconnected part of Earth’s ecosystems, yet they’re vastly underrepresented in research and public consciousness compared to plants and animals. That may change in the future though, as a group of researchers at The Ohio State University have found a way to use fungi as organic memristors — hinting at a possible future where fungal networks help power our computing devices.

A memristor is a passive electronic component whose resistance changes based on the voltage and current that has passed through it, which means it can effectively remember past electrical states even when power is removed. To create these circuit components with fungus, the researchers grew shiitake and button mushroom mycelium for these tests, dehydrated their samples for a number of days, and then attached electrodes to the samples. After misting them briefly to restore conductivity, the samples were exposed to various electrical wave forms at a range of voltages to determine how effective they were at performing the duties of a memristor. At one volt these systems were the most consistent, and they were even programmed to act like RAM where they achieved a frequency of almost 6 kHz and an accuracy of 90%.

In their paper, the research group notes a number of advantages to building fungal-based components like these, namely that they are much more environmentally friendly and don’t require the rare earth metals that typical circuit components do. They’re also easier to grow than other types of neural organoids, require less power, weigh less, and shiitake specifically is notable for its radiation resistance as well. Some work needs to be done to decrease the size required, and with time perhaps we’ll see more fungi-based electrical components like these.

A clay mug is placed on a fire brick. Portions of the mug are glowing orange hot, and the heat is spreading across the surface. Some portions of the mug have cooled, and the heat has not reached other parts.

Thermite Pottery Fires Itself

October 25, 2025 by 28 Comments

Finely powdered aluminium can make almost anything more pyrotechnically interesting, from fireworks to machine shop cleanups – even ceramics, as [Degree of Freedom] discovered. He was experimenting with mixing aluminium powder with various other substances to see whether they could make a thermite-like combination, and found that he could shape a paste of aluminium powder and clay into a form, dry it, and ignite it. After burning, it left behind a hard ceramic material.

[Degree of Freedom] was naturally interested in the possibilities of self-firing clay, so he ran a series of experiments to optimize the composition, and found that a mixture of three parts of aluminium to five parts clay by volume worked best. However, he noticed that bubbles of hydrogen were forming under the surface of the clay, which could cause cracks during the firing. The aluminium was reacting with water to form the bubbles, somewhat like a unwanted form of aerated concrete, and for some reason the kaolinite in clay seemed to accelerate the reaction. Trying to passivate the aluminium by heating it in air or water didn’t prevent the reaction, but [Degree of Freedom] did find that clay extracted from the dirt in his back yard didn’t accelerate it as kaolinite did, and the mixture could dry out without forming bubbles.

This mixture wasn’t totally reliable, so to make it a bit more consistent [Degree of Freedom] added some iron oxide to accelerate the burn through an actual thermite reaction – some mixtures burned hot enough to start to melt the clay. After many tests, he found that sixteen parts clay, seven parts aluminium, and five parts iron oxide gave the best results. He fired two cups made of the mixture, a thin rod, and a cube, with mixed results. The clay expanded a bit during firing, which sometimes produced a rough finish, cracking, and fragility, but in some cases it was surprisingly strong.

The actual chemistry at work in the clay-aluminium mixtures is a bit obscure, but not all thermite reactions need to involve iron oxide, so there might have been some thermite component even in the earlier mixtures. If you need heat rather than ceramic, we’ve also seen a moldable thermite paste extruded from a 3D printer.

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Fail Of The Week: Beaker To Benchy More Bothersome Than Believed

October 20, 2025 by No comments

Making nylon plastic from raw chemicals used to be a very common demo; depending where and when you grew up, you may well have done it in high school or even earlier. What’s not common is taking that nylon and doing something with it, like, say extruding it into filament to make a benchy. [Startup Chuck] shows us there might be a reason for that. (Video, embedded below.)

It starts out well enough: sebacoyl chloride and hexamethaline diamine mix up and do their polymerizing tango to make some nylon, just like we remember. (Some of us also got to play with mercury bare-handed; safety standards have changed and you’ll want to be very careful if you try this reaction at home). The string of nylon [Chuck] pulls from the beaker even looks a little bit like filament for a second, at least until it breaks and gets tossed into a blobby mess. We wonder if it would be possible to pull nylon directly into 1.75 mm filament with the proper technique, but quality control would be a big issue. Even if you could get a consistent diameter, there’d likely be too much solvent trapped inside to safely print.

Of course, melting the nylon with a blowtorch and trying to manually push the liquid through a die to create filament has its own quality control problems. That’s actually where this ends: no filament, and definitely no benchy. [Chuck] leaves the challenge open to anyone else who wants to take the crown. Perhaps one of you can show him how it’s done. We suspect it would be easiest to dry the homemade nylon and shred it into granules and only then extrude them, like was done with polypropylene in this mask-recycling project. Making filament from granules or pellets is something we’ve seen more than once over the years.

If you really want to make plastic from scratch, ordering monomers from Sigma-Aldrich might not cut it for ultimate bragging rights; other people are starting with pulling CO2 from the atmosphere.

Thanks to [Chaz] for the tip! Remember that the tips line isn’t just for your successes– anything interesting can find its home here.

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A Deep Dive Into Molten Bismuth

October 16, 2025 by 2 Comments

Bismuth is known for a few things: its low melting point, high density, and psychedelic hopper crystals. A literal deep-dive into any molten metal would be a terrible idea, regardless of low melting point, but [Electron Impressions]’s video on “Why Do Bismuth Crystals Look Like That” may be the most educational eight minutes posted to YouTube in the past week.

The whole video is worth a watch, but since spoilers are the point of these articles, we’ll let you in on the secret: it all comes down to Free Energy. No, not the perpetual motion scam sort of free energy, but the potential that is minimized in any chemical reaction. There’s potential energy to be had in crystal formation, after all, and nature is always (to the extent possible) going to minimize the amount left on the table.

In bismuth crystals– at least when you have a pot slowly cooling at standard temperature and pressure–that means instead of a large version of the rhombahedral crystal you might naively expect if you’ve tried growing salt or sugar crystals in beakers, you get the madman’s maze that actually emerges. The reason for this is that atoms are preferentially deposited onto the vertexes and edges of the growing crystal rather than the face. That tends to lead to more vertexes and edges until you get the fractal spirals that a good bismuth crystal is known for. (It’s not unlike the mechanism by which the dreaded tin whiskers grow, as a matter of fact.)

Bismuth isn’t actually special in this respect; indeed, nothing in this video would not apply to other metals, in the right conditions. It just so happens that “the right conditions” in terms of crystal growth and the cooling of the melt are trivial to achieve when melting Bismuth in a way that they aren’t when melting, say, Aluminum in the back yard. [Electron Impressions] doesn’t mention because he is laser-focused on Bismuth here, but hopper crystals of everything from table salt to gold have been produced in the lab. When cooling goes to quick, it’s “any port in a storm” and atoms slam into solid phase without a care for the crystal structure, and you get fine-grained, polycrystaline solids; when it goes slowly enough, the underlying crystal geometry can dominate. Hopper crystals exist in a weird and delightful middle ground that’s totally worth eight minutes to learn about.

Aside from being easy to grow into delightful crystals, bismuth can also be useful when desoldering, and, oddly enough, making the world’s fastest transistor.

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A metal needle tip comes to a point against a white background. A scale bar in the lower left shows a 300 micrometer length.

Etching Atomically Fine Needle Points

October 13, 2025 by 22 Comments

[Vik Olliver] has been extending the lower resolution limits of 3D printers with the RepRapMicron project, which aims to print structures with a feature size of ten micrometers. A molten plastic extruder would be impractical at such small scales, even if a hobbyist could manufacture one small enough, so instead [Vik]’s working on a system that uses a very fine needle point to place tiny droplets of UV resin on a substrate. These points have to be sharper than anything readily available, so his latest experiments have focused on electrochemically etching his own needles.

The needles start with a fine wire, which a 3D-printed bracket holds hanging down into a beaker of electrolyte, where another electrode is located. By applying a few volts across the circuit, with the wire acting as an anode, electrochemical erosion eventually wears through the wire and it drops off, leaving an atomically sharp point. Titanium wire performs best, but Nichrome and stainless steel also work. Copper wire doesn’t work, and by extension, nor does the plated copper wire sometimes sold as “stainless steel” by sketchy online merchants.

The electrolyte was made from either a 5% sodium chloride solution or 1% nitric acid. The salt solution produced a very thin, fine point, but also produced a cloudy suspension of metal hydroxides around the wire, which made it hard to tell when the wire had broken off. The goal of nitric acid was to prevent hydroxide formation; it produced a shorter, blunter tip with a pitted shaft, but it simply etched the tip of the wire to a point, with the rest of the wire never dropping off. Some experimentation revealed that a mixture of the two electrolyte solutions struck a good balance which etched fine points like the pure salt solution, but also avoided cloudy precipitates.

If you’re interested in seeing more of the RepRapMicron, we’ve looked at a previous iteration which scribed a minuscule Jolly Wrencher in marker ink. On a more macro scale, we’ve also seen one 3D printer which used a similar resin deposition scheme.

Tube Furnace Is The Real Hotness

September 25, 2025 by 11 Comments

We aren’t sure what [theglassman] is working on, but based on his recent projects, we think it is probably something interesting. He’s been decapping ICs, growing oxide on silicon substrates, and has built a tube furnace capable of reaching 1200 °C.

What would you do with something that can melt cast iron? We aren’t sure, but maybe you’ll tell us in the comments. We do have a fair idea of what [theglassman] is doing, though.

The core of the oven is a quartz tube. Insulation is via refractory cement and alumina ceramic wool. The heating itself is classic Nichrome wire and a tiny thermocouple. The real key, though, is to the proper controller. [theglassman] suggests a ramp/soak controller. These allow you to program sequences that heat up and then stop, which, if done properly, can prevent your fragile quartz tube from cracking.

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