You Wouldn’t Download A Skateboard?

May 30, 2025 by Fenix Guthrie 9 Comments

At the end of the day, a skateboard boils down to a plank of wood with some wheels. They are wonderfully simple and fun and cheap modes of transportation. But this is Hackaday, so we are not here to talk about any normal skateboard, but one you can download and print. [megalog_’s] Skateboard MK2 is made almost entirely of 3D printed plastic, save some nuts and bolts.

The board’s four piece deck comes in at a modest 55cm length and features a rather stylish hexagonal pattern for grip. While you could presumably bring your own trucks, 3D printable ones are provided as well. The pieces bolt together to create a fairly strong deck with the option to make a rather stylish two tone print if you have the printer for it. Where the pieces meet is also the location of the truck mounting, further increasing the board’s strength. The weakest point is where the tail meets the main deck, which if pressed down to wheelie or ollie, the print breaks apart at the layer lines.

While you might be able to bring your own trucks, all be it with some modification to the deck, [megalog] also provided models for those as well. Not only were the bushings made of flexible TPE filament, but the outer wheel tire is too. It’s a little strange to see a wheel tire combo on a skateboard, when they are traditionally over moulded plastic with enough tire that you would be forgiven for thinking there is no wheel. While some reported using the more traditional threaded rod, the trucks used a metal rod with shaft collars to attach the wheels.

This is a neatly executed skateboard build with a well thought out design. Let us know in the comments if you will (or have) made one yourself! While you’re at it, maybe cast your own resin wheels for it!

Reverse Engineering LEGO Island

May 24, 2025 by Fenix Guthrie 4 Comments

While LEGO themed video games have become something of a staple, in 1997 they were something of an odity. LEGO Island became the first LEGO video game released outside of Japan in 1997 and become something of a hit with over one million copies sold. The game was beloved among fans and set the stage for more LEGO video games to come. In an effort of love, [MattKC] put together a team to reverse engineer the game.

The team set out with the intent to create a near perfect recreation of the codebase, relying on custom made tools to run byte checks on the rewrite compilation and the original binary. While the project is functionally complete, [MattKC] believes it is impossible to get a byte accurate codebase. This is because of what the team called “compiler entropy.” Strange behaviors exists inside of Microsoft’s Visual C++ compiler of the era, and small changes in the code have seemingly random effects to unrelated parts of the binary. To mitigate this issue would likely require either partially reverse engineering Visual C++ or brute forcing the code, both of which would take a large amount of effort and time for no real benefit.

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A Look Inside A Lemon Of A Race Car

May 21, 2025 by Fenix Guthrie 7 Comments

Automotive racing is a grueling endeavor, a test of one’s mental and physical prowess to push an engineered masterpiece to its limit. This is all the more true of 24 hour endurance races where teams tag team to get the most laps of a circuit in over a 24 hour period. The format pushes cars and drivers to the very limit. Doing so on a $500 budget as presented by the 24 hours of Lemons makes this all the more impressive!

Of course, racing on a $500 budget is difficult to say the least. All the expected Fédération Internationale de l’Automobile (FIA) safety requirements are still in place, including roll cage, seats and fire extinguisher. However, brakes, wheels, tires and safety equipment are not factored into the cost of the car, which is good because an FIA racing seat can run well in excess of the budget. Despite the name, most races are twelve to sixteen hours across two days, but 24 hour endurance races are run. The very limiting budget and amateur nature of the event has created a large amount of room for teams to get creative with car restorations and race car builds.

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You Wouldn’t Download A Helmet?

May 13, 2025 by Fenix Guthrie 33 Comments

Odds are, if you have ridden a bicycle for any amount of time, you have crashed. Crashes are fast, violent and chaotic events that leave you confused, and very glad to have a helmet. But what if there was another way of protecting your head? [Seth] decided to find out by taking a look at the Hövding airbag helmet.

The Hövding sits around your neck and looks somewhat akin to a neck pillow. It uses accelerometers situated in the fore and aft of the device to detect what it thinks is a crash. If a crash is detected, it will release a charge of compressed helium to inflate an airbag that wraps around the user’s head protecting a larger amount of the head then a traditional helmet. It also inflates around the wearer’s neck providing neck bracing in the impact further improving safety. The inflation process is incredibly fast and violent, very much akin to a car’s airbag. [Seth] demonstrated this on the process on two occasions to great effect, and to his amazement. While the idea of relying on computers to protect your head may sound ridiculous, studies have shown that the Hövding is safer than a regular helmet in certain situations.

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Terminal DAW Does It In Style

April 30, 2025 by Fenix Guthrie 30 Comments

As any Linux chat room or forum will tell you, the most powerful tool to any Linux user is a terminal emulator. Just about every program under the sun has a command line alternative, be it CAD, note taking, or web browsing. Likewise, the digital audio workstation (DAW) is the single most important tool to anyone making music. Therefore, [unspeaker] decided the two should, at last, be combined with a terminal based DAW called Tek.

Tek functions similarly to other DAWs, albeit with keyboard only input. For anyone used to working in Vim or Emacs (we ask you keep the inevitable text editor comment war civil), Tek will be very intuitive. Currently, the feature set is fairly spartan, but plans exist to add keybinds for save/load, help, and more. The program features several modes including a multi-track sequencer/sampler called the “arranger.” Each track in the arranger is color coded with a gradient of colors generated randomly at start for a fresh look every time.

Modern audio workflows often span across numerous programs, and Tek was built with this in mind. It can take MIDI input and output from the JACK Audio Connection Kit, and plans also exist to create a plugin server so Tek could be used with other DAWs like Ardor or Zrythm. Moreover, being a terminal program opens possibilities for complicated shell scripting and other such Linux-fu.

Maybe a terminal DAW is not your thing, so make sure to check out this physical one instead!

EInk PDA Revisited

April 22, 2025 by Fenix Guthrie 23 Comments

In the dark ages, before iOS and Android phones became ubiquitous, there was the PDA. These handheld computers acted as simple companions to a computer and could often handle calendars, email, notes and more. Their demise was spelled by the smartphone, but the nostalgia of having a simple handheld and romanticizing about the 90’s and 2000’s is still there. Fortunately for the nostalgic among our readers, [Ashtf] decided to give us a modern take on the classic PDAs.

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Bicycle Gearbox Does It By Folding

April 17, 2025 by Fenix Guthrie 52 Comments

If you’ve spent any time on two wheels, you’ve certainly experienced the woes of poor bicycle shifting. You hit the button or twist the knob expecting a smooth transition into the next gear, only to be met with angry metallic clanking that you try to push though but ultimately can’t. Bicycle manufacturers collectively spent millions attempting to remedy this issue with the likes of gearboxes, electronic shifting, and even belt-driven bikes. But Praxis believes to have a better solution in their prototype HiT system.

Rather then moving a chain between gears, their novel solution works by folding gears into or away from a chain. These gears are made up of four separate segments that individually pivot around an axle near the cog’s center. These segments are carefully timed to ensure there is no interference with the chain making shifting look like a complex mechanical ballet.

While the shift initialization is handled electronically, the gear folding synchronization is mechanical. The combination of electronic and mechanical systems brings near-instant shifting under load at rotational rates of 100 RPM. Make sure to scroll through the product page and watch the videos showcasing the mechanism!

The HiT gearbox is a strange hybrid between a derailleur and a gearbox. It doesn’t contain a clutch based gear change system or even a CVT as seen in the famous Honda bike of old. It’s fully sealed with more robust chains and no moving chainline as in a derailleur system. The prototype is configurable between four or sixteen speeds, with the four speed consisting of two folding gear pairs connected with a chain and the sixteen speed featuring a separate pair of folding gears. The output is either concentric to the input, or above the input for certain types of mountain bikes.

Despite the high level of polish, this remains a prototype and we eagerly await what Praxis does next with the system. In the meantime, make sure to check out this chainless e-drive bicycle.