Designing And Building A Custom Optical Fuel Sensor

At some time or another, we’ve all had an idea we thought was so clever that we jumped on the Internet to see if somebody else had already come up with it. Most of the time, they have. But on the off chance that you can’t find any signs of it online, you’re left with basically two possible conclusions. Either you’re about to enter uncharted territory, or your idea is so bad that everyone has collectively dismissed it already.

Which is precisely where [James Stanley] recently found himself. He had an idea for an non-contact optical sensor which would detect when his racing mower was about to run out of gas by analyzing light passed through a clear section of fuel hose. He couldn’t find any previous DIY examples of such a device, nor did there appear to be a commercial version. But did that mean it wouldn’t work, or that nobody had ever tried before?

Continue reading “Designing And Building A Custom Optical Fuel Sensor”

HALWOP Recreates Retro Style With The Raspberry Pi

Modern computers are incredible feats of engineering, but there are many that still yearn for the simpler times. When keyboards clacked and a desktop computer quite literally dominated the top of your desk. There’s a whole community of folks who scratch that itch by restoring vintage computers, but not everyone has the time, money, or skill for such pursuits. Plus, even the most lovingly cared for Apple II isn’t going to help you watch YouTube.

Those who wish to recreate the look and feel of a vintage computer with modern internals will certainly be interested in the HALWOP by [Maz_Baz]. While its 3D printed case isn’t a replica of any one computer, it does draw inspiration from iconic machines like the Apple Lisa and IBM XT. It’s an amalgamation of design ideas that seemed like a good idea circa 1982 or so, with plenty of 90° angles and air vents to go around.

Considering the size of the Raspberry Pi 4 that powers the HALWOP, most of the case is just hollow plastic. But of course, the whole idea depends on it being almost comically large. On the plus side, [Maz_Baz] says you can use one of those empty compartments to hold a Anker PowerCore 26800 battery pack. At least in theory that makes it a “luggable” computer, though good luck trying to move it around.

In addition to the Pi 4 and battery pack, the HALWOP also uses a seven-inch touch LCD and Keychron K2 Bluetooth mechanical keyboard. Since everything is so modular, assembly is about as simple as it gets. Outside of the USB cables that power everything, you just need a long enough ribbon cable to connect the LCD to the Pi.

We know the purists don’t like the idea of a “retro” computer based on the Raspberry Pi, but of course, such projects aren’t about maintaining historical accuracy. They are a way to bridge the gap between modern technology and the unique aesthetics of a bygone era. Designs like the HALWOP allow a new generation to experience a taste of what computing was like in the early days, without giving up the ground that’s been gained in the intervening years.

3D Printed Mini MacBook With A Raspberry Pi Heart

Do you like the sleek look of Apple’s laptops? Are you a fan of the Raspberry Pi? Have a particular affinity for hot glue and 3D printed plastic? Then you’re in luck, because this tiny “MacBook” built by serial miniaturizer [Michael Pick] features all of the above (and a good bit more) in one palm-sized package. (Video link, embedded below.)

Getting the LCD panel and Raspberry Pi 4 to fit into the slim 3D printed case took considerable coaxing. In the video after the break, you can see [Michael] strip off any unnecessary components that would stand in his way. The LCD panel had to lose its speakers and buttons, and the Pi has had its Ethernet and USB ports removed. While space was limited, he did manage to squeeze an illuminated resin-printed Apple logo into the lid of the laptop to help sell the overall look.

The bottom half of the machine has a number of really nice details, like the fan grill cut from metal hardware cloth and a functional “MagSafe” connector made from a magnetic USB cable. The keyboard PCB and membrane was liberated from a commercially available unit, all [Michael] needed to do was model in the openings for the keys. Since the keyboard already came with its own little trackpad, the lower one is just there for looks.

Speaking of which, to really drive home the Apple aesthetic, [Michael] made the bold move of covering up all the screws with body filler after assembly. It’s not a technique we’d necessarily recommend, but gluing it shut would probably have made it even harder to get back into down the line.

We’ve previously seen [Michael] create a miniature rendition of the iMac and an RGB LED equipped “gaming” computer using many of the same parts and techniques. He’ll have to start branching off into less common machines to replicate soon, which reminds us that we’re about due for another tiny Cray X-MP.

Continue reading “3D Printed Mini MacBook With A Raspberry Pi Heart”

3D Printed Video Terminal Dials C For Cyberpunk

Created for the Disobey 2020 hacker conference in Finland, this Blade Runner inspired communications terminal isn’t just for decoration. It was part of an interactive game that required attendees to physically connect their conference badges up and “call” different characters with the functional keypad on the front of the unit.

[Purkkaviritys] was in charge of designing the 3D printed enclosure for the device, which he says takes an entire 2 kg roll of filament to print out. Unfortunately he wasn’t as involved in the electronics side of things, so we don’t have a whole lot of information about the internals beyond the fact that its powered by a Raspberry Pi 4, features a HyperPixel 4.0 display, and uses power over Ethernet so it could be easily set up at the con with just a single cable run.

A look at the custom keypad PCB.

The keypad is a custom input device using the Arduino Micro and Cherry MX Blue switches with 3D printed keycaps to get that chunky payphone look and feel. [Purkkaviritys] mentions that the keypad is also responsible for controlling the RGB LED strips built into the sides of the terminal, and that the Raspberry Pi toggles the status of the Caps, Scroll Lock, and Num Lock keys to select the different lighting patterns.

Naturally we’d like to see more info on how this beauty was put together, but given that it was built for such a specific purpose, it’s not like you’d really need to duplicate the original configuration anyway. Thanks to [Purkkaviritys] you have the STL files to print off our own copy of the gloriously cyberpunk enclosure, all you’ve got to do now is figure out how to make video calls with it.

Continue reading “3D Printed Video Terminal Dials C For Cyberpunk”

Radon Monitor Recreates Steam Gauge With E-Ink

While the full steampunk aesthetic might be a bit much for most people, those antique gauges do have a certain charm about them. Unfortunately, implementing them on a modern project can be somewhat tricky. Even if you’ve got a stock of old gauges laying around, you’ve still got to modify the scale markings and figure out how to drive them with digital electronics. While we’ve seen plenty of people do it over the years, there’s no debating it’s a lot harder than just wiring up an I2C display.

But maybe it doesn’t have to be. With his Rad-O-Matic, [Hans Jørgen Grimstad] created a pretty convincing “analog” gauge using a small e-ink panel. Of course it won’t fool anyone who gives it a close look, but at a glance, you could certainly be forgiven for thinking it was some kind of vintage indicator. Especially with the cracked and stained Fresnel lens he put in front of it.

For this project [Hans] used a LilyGo T5, which combines an ESP32 with a 2.13 inch electronic paper display. These are presumably meant to be development boards for digital signage applications, but they occasionally show up in hacker projects since they’re so easy to work with. The board pulls data from a RD200M radon sensor over a simple UART connection, and the current reading is indicated by a “needle” that moves across a horizontal scale on the display.

On its own, it wouldn’t look very vintage. In fact, quite the opposite. But [Hans] really helped sell the look on this project by designing and 3D printing a chunky enclosure and then weathering it to make it look like it’s been kicking around since the Cold War.

If you don’t feel like faking it, we’ve seen some very impressive projects based on authentic vintage gauges. As long as you don’t mind tearing up hardware that’s likely older than you are, putting in the extra effort necessary for a convincing modification can really pay off.

[Thanks to Tarjei for the tip.]

A Cyclopic LCD Case For Your Raspberry Pi Server

If you’ve got a personal website that needs hosting or a few hundred gigabytes of files that could use a centralized storage location, the Raspberry Pi’s small size and extreme energy efficiency make it a compelling server choice compared to that curbside Pentium 4 box you’ve been trying to find a home for. All you need is something to put in.

Of course there’s no shortage of Pi case designs ready to be extruded from your 3D printer, but we recently found ourselves particularly taken with this unique one designed by [Ken Segler]. It’s not only small and sleek with a dash of futuristic flair, but it includes a front-mounted two inch 240 x 320 IPS display that connects to the Pi over SPI. At the minimum that gives you a way to see all those beautiful boot messages on startup, but with a little code, it could provide you with various system statics and status messages at a glance.

While the LCD is clearly the star of the show here, the case also has a few other nice features that make it worthy of your consideration. The magnetically attached fan filter on the the top, for one. The stacked layout that puts the Pi directly above the SSD also makes for a relatively compact final product.

One thing to note though is that [Ken] is using Power-over-Ethernet, meaning there’s no spot for a dedicated power jack on the case. It’s an easy enough feature to add into your own build, but naturally not everyone’s network is suitably equipped. In that case, beyond the normal annoyances of editing STL files, it shouldn’t be too much trouble to add one in without having to literally hack your way through the printed plastic.

Mil-Spec Looks Without Defense Department Budget

While hackers and makers have a tendency to focus on functionality above all else, that doesn’t mean there isn’t room for some visual flair. A device that works well and looks good will always be more impressive than the bare bones approach, but the extra time and money it usually takes to polish up the visual component of a build means it’s often overlooked. Which is exactly what [Jay Doscher] wanted to address with his Mil-Plastic project.

On the surface, the Mil-Plastic is yet another entry in the rapidly growing and often ill-defined world of cyberdecks: custom computing devices that forgo the standard laptop and desktop dichotomy and instead explore the road not taken by mainstream consumer electronics. To that end, it’s a solid build more than worthy of praise. But more than that, it’s also a lesson on how 3D printing and some clever design can create a truly impressive visual for little more than the cost of a spool of PLA.

The modular design allows parts to be printed in parallel.

The Mil-Plastic, as the name implies, looks like it was pulled from a Humvee or an Abrams tank. While the gorgeous olive green PETG filament that [Jay] has stumbled upon certainly helps, his eye for detail and design chops aren’t to be underestimated. He’s given the case a rugged and armored look that simply screams “Your Tax Dollars At Work”, complete with faux cooling fins running along the back and a generous application of low-profile stainless steel fasteners. We’ve taken a close look at the decadence of military engineering in the past, and the Mil-Plastic could hang with the best of them.

Most importantly, [Jay] has given us all the tools and information we need to recreate the look on our own terms. You don’t have to be in the market for yet another Raspberry Pi gadget to appreciate the Mil-Plastic; the design can serve as the backbone for whatever you happen to be building. The printed case not only looks impressive, but can easily be modified and expanded as needed.

[Jay] kicked off a minor revolution late last year with his Raspberry Pi Recovery Kit, and has continued to produce well-documented designs that illustrate the incredible power of desktop 3D printing. If you can look through his portfolio and not get inspired, you may want to speak with a doctor.