TechyMagThings

In 2024, [Jan Roetz] decided to see whether he could 3D print a Benchy – the boat-shaped benchmarking tool used in 3D printer calibration – in less than one minute. Two years later, after experiments with air bearing print beds, dry ice cooling, multi-filament hotends, and more, he’s finally broken the one-minute mark.

There are three primary factors limiting the speed of the printer: the extrusion flow rate, the cooling rate for extruded plastic, and the motion system itself. The printer’s hotend combines four strands of filament in one hotend and can extrude about 400 cubic millimeters of plastic per second. For cooling, an air duct around the nozzle could deliver about 400 liters of air per minute, which left the motion system as the only bottleneck.

The original print bed was on top of an air bearing on a granite base, and its motion could be controlled by cords connected to stepper motors. This whole system had very low friction, but its inertia was too high. [Jan] therefore replaced the build plate with a lighter carbon-fiber frame. This had no air bearing, but it slid between the base granite slab and a glass plate above it, which had an opening above the portion used as a build plate. Even the metal pulleys used on the stepper motors had too much inertia, so [Jan] replaced them with smaller, semi-circular plastic pulleys.

The first test was a sub-60-second dry run to make sure nothing would break. This revealed the need for cable guides to keep them from whipping around (not surprising when they were pulling the bed at an acceleration of 225 G). Finally, [Jan] was able to successfully print several successive 59-second Benchies. The prints weren’t photogenic, but they were mechanically sound and dimensionally correct. [Jan] could have gone even faster, but this degraded the print quality too much.

It’s quite an accomplishment, and an impressive conclusion to a major project; we covered the beginning of the project back when [Jan] was going for parallelization rather than speed. The final print didn’t use it, but he also experimented with dynamic temperature control.

You would think a guitar amplifier would be a straightforward piece of analog electronics. But, of course, these days, everything has firmware, including [mforney]’s Yamaha THR10c. The service manual showed both a UART and JTAG header on the schematic, so as many of us would, he took that as a challenge.

Of course, the production board doesn’t have headers for these ports, but that’s not a real problem. The serial port seemed quiet, but the JTAG port was more productive. This revealed two binary images: a bootloader and the main firmware. Once you have the code, it is a straightforward, if not laborious, process to reverse engineer what the code does.

The next step is to figure out how to load new firmware. You can see in the post that this was done, and custom features sprang into life with custom-patched firmware.

We never get tired of seeing people dig into consumer devices like this. Things like JTAG and the wide availability of JTAG tools have made it easier but no less fun. Of course, there are even more features [mforney] has in mind, but now that’s just a matter of coding.

Mini game controllers with buttons and joysticks that move like the real deal are a pretty cool keychain and fidget toy, but at least for some of us there’s this intrusive thought that tells us that it would be so much cooler if it actually was a functional game controller. Enter [Brux] tearing into a miniature GameCube controller and adding the required guts.

The keychain/fidget toy is made by Backpack Buddies and is one of a range of similar toys that feature buttons you can press and joysticks that move, giving a pretty good start on the externals of the controller. Once cracked open at the seam, some interior redecorating had to be performed to clear space and add something to mount switches onto. Here [Brux] opted to glue SMD switches to custom 3D components in lieu of a PCB. These were subsequently wired up with thin enameled wire, before attaching the original buttons to them following some more plastic surgery.

Some tiny joystick innards were then installed before gluing on the final buttons and joystick caps. As for how it all connects to a real GameCube, here an RP2040 was used to handle the translation of control inputs to the GameCube controller protocol. Then a GameCube controller was sacrificed for its cable and controller connector, but as can be seen in the video it does all work and creates the perfect controller for guests.

The pioneering work done by Alan Turing and others at Bletchley Park in England was perhaps as important in the history of technology as it was the history of the war. Given the last 80-odd years of technological development, their revolutionary work should be within the realms of a student project — which it was, specifically in ECE 5760 at Cornell University. The work was done by [Erica Jiang], [Kelvin Resch], and [Isabella Frank].

Nowadays if someone told you there was a code to be broken, you wouldn’t be reaching for electromechanical devices, but you just might think of trying an FPGA. After all, the programmable gate arrays allow for much faster execution of fixed logic than software running on a traditional CPU. That won’t help much with modern RSA schemes, and for Enigma, it’s massively overkill, but doing it that way was a great learning opportunity for the students.

Their project emulates the whole Bletchley Park cryptography apparatus, not just the Bombe Machine, and if you’re interested in learning about this piece of history you could absolutely do worse than to examine their documentation. If you’re into video, you can check out the final presentation and demo video below. Meanwhile if you’re wondering what the opposition was up to, we have good explainer of the enigma machine here.

Thanks to [Hunter Adams] for the tip!

Plastics, oil, petrol– the modern world is entirely dependent on hydrocarbons. The good sources are slowly running low and supply is increasingly complicated by geopolitical factors we really don’t want to get into, but hey! It’s just hydrogen and carbon, right like it says in the name. How hard could it be to roll your own at home. Well, if you’ve got a lab like [Marb]’s Lab on YouTube, it might just be doable, as he demonstrates in his latest video.

The Fischer-Tropsch reaction was discovered back in 1925 in Germany by a couple of gents named Fischer and Tropsch. In the unpleasantness that followed later, Germany made good use of their process on an industrial scale, since they had ample coal and no oil on hand. Coal-rich South Africa has also made us of it, particularly during the Apartheid-era trade restrictions. Every so often the idea of industrializing the process comes up in the USA, but there’s still enough oil there it doesn’t make sense economically.

Those nations all have something in common: they’re all coal-rich countries, and that makes sense because coal is easily converted to carbon monoxide and hydrogen– a combo known as syngas– and it just so happens that those are the feedstock for this reaction. The actual chemistry going on inside is quite complex, but conceptually it is pretty simple: hydrogen and carbon monoxide mix over a hot metal catalyst, and combine to form various hydrocarbons.

In [Marb]’s glassware-based demonstration, the catalyst is Cobalt (III) Oxide on silica gel– a lovely, cancer-causing substance that must be prepared for each use, as it lasts but 24 hours before further oxidization ruins it. That’s in spite of purging the system with argon– a necessary step if one does not wish to explode. The yield isn’t amazing, and [Marb] isn’t sure exactly what mix of hydrocarbons he has created– although they smell like gasoline and burn like the dickens, so mission accomplished.

This might seem like the furthest thing from green, but if you use solar power to run the process and something like woodgas– which is syngas by any other name– as a feed-stock, then you’ve got a carbon neutral energy storage medium.

Thanks to [Markus Bindhammer] for the tip!

If you’re of a certain vintage, you have probably looked at some of the microcomputers on the market these days and thought “that would have been a decent workstation back in the day!”. We certianly have, and so did [Roberto Alsina]. Rather than allow himself to contemplate his age and threfore rapidly approaching mortailty, [Roberto] wrote a useful operating system called ESP-Osito for the Cheap Yellow Display, which he refers to as “the cheapest computer”. He’s not wrong, and it’s certainly a better use of time than an existential crisis.

He explains some of his reasoning behind the project in an accompanying blog post, but on the project page he compares it to a Palm Pilot– it’s on quick, apps load quick, and the API is simple enough for easy app creation in a few hundred lines of C, unlike certain pocket computers we won’t name. Sure, there’s no multitasking, but when apps jump from SD card to run in memory in microseconds, who cares? Saving the current state of the app back to SD means the experience is virtually identical from a user perspective anyway.

As this is a one-man show for now, the app store won’t quite rival your smart phone– but there’s everything you’d expect on the 90s-era computer this has the horsepower of: a serial terminal, a text editor, a file explorer, a calculator, a clock, but also some things that aren’t so retro. The clock app gives weather info via futuristic wireless networking, the reader app takes Markdown text, and the chat app connects to an LLM somewhere instead of your friends on IRC. The blackberry keyboard option gives it a feel of a slightly different vintage. You can also play snake, because no computer is complete without games. The OS and all its applications are released under the MIT license on GitHub, and [Roberto] is actively looking for collaborators.

If you doubt the workstation comparison at the start of this article, this CYD runs Macintosh System 3 via a 68k emulator. That’s got old-school cred, but there’s something great about having retro constraints with modern code on modern hardware. In that way, ESP-Osito is similar to the 3D graphics engine behind this Wipeout clone.

Ever since wealthy European landowners started displaying vast, unused swaths of turfgrass as status symbols, regular folk have been chasing that perfectly mown and tended lawn for similar reasons. In the modern era, most mowers used to maintain these spaces use a spinning blade attached to a motor of some sort, but this can be dangerous especially on rocky fields like [Greenhill Forge] needs to mow. For these fields it’s best to use a different type of mower, and he’s built one from scratch.

This type of mower is called a flail mower, which has hinged, sharpened hammers attached to a central rotating drum. Since the flails have less rotational speed at the ends, they are less dangerous if they strike solid objects like rocks. To build one, he first builds the central drum and flails, then the enclosure to mount it to his tractor, and then a drivetrain to attach it to the tractor’s PTO. Since everything is getting built in [Greenhill Forge]’s metalworking shop, many of the parts needed to be fabricated from scratch, which involved several jigs for the plasma cutter as well as forging some steel to make some of the thicker parts.

Although not many of us have fully-stocked metalworking shops like this, it shows that almost anything can be built with the right tools. A forge is actually fairly accessible for those looking to start smithing; we’ve seen them built from little more than an off-the-shelf unmodified microwave or from a propane torch and some cookware.