Mining And Refining: From Red Dirt To Aluminum

December 13, 2021 by Dan Maloney 29 Comments

No matter how many syllables you use to say it, aluminum is one of the most useful industrial metals we have. Lightweight, strong, easily alloyed, highly conductive, and easy to machine, cast, and extrude, aluminum has found its way into virtually every industrial process and commercial product imaginable.

Modern life would be impossible without aluminum, and yet the silver metal has been in widespread use only for about the last 100 years. There was a time not all that long ago that aluminum dinnerware was a status symbol, and it was once literally worth more than its weight in gold. The reason behind its one-time rarity lies in the effort needed to extract the abundant element from the rocks that carry it, as well as the energy to do so. The forces that locked aluminum away from human use until recently have been overcome, and the chemistry and engineering needed to do that are worth looking into in our next installment of “Mining and Refining.”

Continue reading “Mining And Refining: From Red Dirt To Aluminum” →

Own The Night With This Ludicrously Bright DIY Flashlight

November 8, 2021 by Dan Maloney 27 Comments

If you’re a flashlight person, you know that there’s little you would do to get the brightest, most powerful, most ridiculous flashlight possible. You might even decide to build yourself a ludicrously powerful flashlight, like [Maciej Nowak] did.

If you choose the DIY route, be warned that it’s probably not going to be a simple process, at least if you follow [Maciej]’s lead. His flashlight is machined out of aluminum rounds, all turned down on the lathe to form the head of the flashlight. The head is made from three parts, each of which acts as a heat sink for the five 20-Watt CREE XHP70 LED modules. The LEDs are mounted with care to thermal considerations, and wired in series to DC-DC converter that provides the necessary 30 V using a battery pack made from four 21700 Li-ion cells. The electronics, which also includes a BMS for charging the battery and a MOSFET switching module, form a tidy package that fits into the aluminum handle.

The video below shows that the flashlight is remarkably bright, with a nice, even field with no hotspots. Given the 45-minute useful life and the three-hour recharge time, it might have been nice to make it so anywhere from one to five of the LEDs could be turned on at once. Some interesting effects might be had from switching the LEDs on sequentially, too.

Given the proclivities of our community, it’s no surprise that this is hardly the first powerful flashlight we’ve seen. This one broke the 100-Watt barrier with a single COB LED, while this ammo-can version sports an even higher light output. Neither of them looks much like a traditional flashlight, though, which is where [Maciej]’s build has the edge.

Continue reading “Own The Night With This Ludicrously Bright DIY Flashlight” →

Magnesium: Where It Comes From And Why We’re Running Out

November 1, 2021 by Adam Zeloof 94 Comments

Okay, we’re not running out. We actually have tons of the stuff. But there is a global supply chain crisis. Most of the world’s magnesium is processed in China and several months ago, they just… stopped. In an effort to hit energy consumption quotas, the government of the city of Yulin (where most of the country’s magnesium production takes place) ordered 70% of the smelters to shut down entirely, and the remainder to slash their output by 50%. So, while magnesium remains one of the most abundant elements on the planet, we’re readily running out of processed metal that we can use in manufacturing.

Nikon camera body — The magnesium-alloy body of a Nikon d850. Courtesy of Nikon

But, how do we actually use magnesium in manufacturing anyway? Well, some things are just made from it. It can be mixed with other elements to be made into strong, lightweight alloys that are readily machined and cast. These alloys make up all manner of stuff from race car wheels to camera bodies (and the chassis of the laptop I’m typing this article on). These more direct uses aside, there’s another, larger draw for magnesium that isn’t immediately apparent: aluminum production.

But wait, aluminum, like magnesium is an element. So why would we need magnesium to make it? Rest assured, there’s no alchemy involved- just alloying. Much like magnesium, aluminum is rarely used in its raw form — it’s mixed with other elements to give it desirable properties such as high strength, ductility, toughness, etc. And, as you may have already guessed, most of these alloys require magnesium. Now we’re beginning to paint a larger, scarier picture (and we just missed Halloween!) — a disruption to the world’s aluminum supply.

Continue reading “Magnesium: Where It Comes From And Why We’re Running Out” →

Making Coffee With Hydrogen

October 9, 2021 by Jenny List 17 Comments

Something of a Holy Grail among engineers with an interest in a low-carbon future is the idea of replacing fossil fuel gasses with hydrogen. There are various schemes, but they all suffer from the problem that hydrogen is difficult stuff to store or transport. It’s not easily liquefied, and the tiny size of its molecule means that many containment materials that are fine for methane simply won’t hold on to it.

[Isographer] has an idea: to transport the energy not as hydrogen but as metallic aluminium, and generate hydrogen by reaction with aqueous sodium hydroxide. He’s demonstrated it by generating enough hydrogen to make a cup of coffee, as you can see in the video below the break.

It’s obviously very successful, but how does it stack up from a green perspective? The feedstocks are aluminium and sodium hydroxide, and aside from the hydrogen it produces sodium aluminate. Aluminium is produced by electrolysis of molten bauxite and uses vast amounts of energy to produce, but since it is often most economic to do so using hydroelectric power then it can be a zero-carbon store of energy. Sodium hydroxide is also produced by an electrolytic process, this time using brine as the feedstock, so it also has the potential to be produced with low-carbon electricity. Meanwhile the sodium aluminate solution is a cisutic base, but one that readily degrades to inert aluminium oxide and hydroxide in the environment. So while it can’t be guaranteed that the feedstock he’s using is low-carbon, it’s certainly a possibility.

So given scrap aluminium and an assortment of jars it’s possible to make a cup of hot coffee. It’s pretty obvious that this technology won’t be used in the home in this way, but does that make it useless? It’s not difficult to imagine energy being transported over distances as heavy-but-harmless aluminium metal, and we’re already seeing a different chemistry with the same goal being used to power vehicles.

Continue reading “Making Coffee With Hydrogen” →

Small low-cost CNC mill with rotary tool

Minimal Mill: The Minamil

September 10, 2021 by Bryan Cockfield 35 Comments

Having a few machine tools at one’s disposal is a luxury that not many of us are afforded, and often an expensive one at that. It is something that a large percentage of us may dream about, though, and with some commonly available tools and inexpensive electronics a few people have put together some very inexpensive CNC machines. The latest is the Minamil, which uses a rotary tool and straps it to an economical frame in order to get a functional CNC mill setup working.

This project boasts impressively low costs at around $15 per axis. Each axis uses readily available parts such as bearings and threaded rods that are readily installed in the mill, and for a cutting head the build is based on a Dremel-like rotary tool that has a similarly low price tag. Let’s not ignore the essentially free counterweight that is used.

For control, an Arduino with a CNC shield powers the three-axis device which is likely the bulk of the cost of this project. [Paul McClay] also points out that a lot of the material he needed for this build can be salvaged from things like old printers, so the $45 price tag is a ceiling, not a floor.

The Minamil has been demonstrated milling a wide variety of materials with excellent precision. Both acrylic and aluminum are able to be worked with this machine, but [Paul] also demonstrates it in its capacity to mill PCBs. It does have some limitations but for the price it seems that this mill can’t be beat, even compared to his previous CNC build which repurposed old CD drives.

You Can’t Put The Toothpaste Back In The Tube, But It Used To Be Easier

June 24, 2021 by Kristina Panos 60 Comments

After five years of research, Colgate-Palmolive recently revealed Australia’s first recyclable toothpaste tube. Why is this exciting? They are eager to share the design with the rest of the toothpaste manufacturers and other tube-related industries in an effort to reduce the volume of plastic that ends up in landfills. It may not be as life-saving as seat belts or the Polio vaccine, but the move does bring Volvo and OG mega open-sourcer Jonas Salk to mind.

Today, toothpaste tubes are mostly plastic, but they contain a layer of aluminum that helps it stay flattened and/or rolled up. So far, multi-layer packaging like this isn’t accepted for recycling at most places, at least as far as Australia and the US are concerned. In the US, Tom’s of Maine was making their tubes entirely out of aluminum for better access to recycling, but they have since stopped due to customer backlash.

Although Colgate’s new tubes are still multi-layered, they are 100% HDPE, which makes them recyclable. The new tubes are made up of different thicknesses and grades of HDPE so they can be easily squeezed and rolled up.

Toothpaste Before Tubes

Has toothpaste always come in tubes? No it has not. It also didn’t start life as a paste. Toothpaste has been around since 5000 BC when the Egyptians made tooth powders from the ashes of ox hooves and mixed them with myrrh and a few abrasives like powdered eggshells and pumice. We’re not sure what they kept it in — maybe handmade pottery with a lid, or a satchel made from an animal’s pelt or stomach.

The ancient Chinese used ginseng, salt, and added herbal mints for flavoring. The Greeks and Romans tried crushed bones, oyster shells, tree bark, and charcoal, which happens to be back in vogue. There is evidence from the late 1700s showing that people once brushed with burnt breadcrumbs.

Continue reading “You Can’t Put The Toothpaste Back In The Tube, But It Used To Be Easier” →

Gorgeous 6502 Celebrates Craftsmanship Of The Early Homebrewers

April 21, 2021 by Dan Maloney 36 Comments

The days when a computer had a front panel bristling with switches and LEDs are long gone, and on balance that’s probably for the better in terms of ease of use, raw power, and convenience. That’s not to say there aren’t those who long for the days of flipping switches to enter programs, of course, but it’s a somewhat limited market. So unless you can find an old IMSAI or Altair, chances are you’ll have to roll your own — and you could do a lot worse than this aluminum beauty of a 6502 machine.

The machine is named PERSEUS-8 by its creator, [Mitsuru Yamada]. It follows earlier machines bearing the PERSEUS badge, all of them completely homebrewed and equally gorgeous. The PERSEUS-8 would have been an impressive machine had it come along 45 years ago — the 2 MHz version of the 6502, a full 16-bit memory address space, and 16 kB of battery-backed RAM. But the mechanical and electrical construction methods and the care and craftsmanship taken are where this build really shines. The case is fabricated out of aluminum sheets and angles and looks like it could have come from a server rack. The front panel is to die for — [Mitsuru] carefully brushed the aluminum before drilling the dozens of holes needed for the toggle switches and LEDs. And the insides are equally lovely — socketed chips neatly arranged on perfboard with everything wired up using period-correct wirewrap methods. Even the labels, both on the front panel and even on the motherboard, are a joy to behold.

Builds like this are the ones that really inspire us to take the extra steps needed to make our projects not only work, but also to be beautiful. We’ve seen this kind of craftsmanship from [Mitsuru] before — recall this serial terminal that never was, or the machine that came before the PERSEUS-8.