2026-02-20 02:00:43
We are going to bet that as a kid, you had a View-Master. This toy has been around for decades and is, more or less, a handheld stereoscope. We never thought much about the device’s invention until we saw a recent video from [View Master Travels and Peter Dibble]. It turns out that the principle of the whole thing was created by the well-known [Charles Wheatstone]. However, it was piano repairman [William Gruber] who invented what we think of as the View-Master.
[Gruber] didn’t just work on normal pianos, but complex player pianos and, in particular, the pianos used to record player piano rolls. He was also, as you might expect, a stereo photography enthusiast. Many of the ideas used in automating pianos would show up in the View-Master and the machines that made the reels, too. In the 1930s, stereoscopes were not particularly popular and were cumbersome to use. Color film was also a new technology.
[Gruber] realized that a disk-like format would be easy to use and, more importantly, easy to mass produce. The reels had a few features to simplify their use. For example, if you show each image in sequence, you’d eventually see pictures upside down. [Gruber’s] solution? Use an odd number of pairs and advance the reel two positions for each jump forward. That way, you never show an image to the wrong eye.
The model “A” didn’t look much like the View-Master you probably remember. By 1940, the toy was a hit. But initially, it wasn’t really a toy so much as a way for adults to view distant sites. Of course, World War II could have stopped the enterprise dead, but instead, they shifted to producing training aids for the military. The War Department would buy 100,000 viewers and about 6 million reels to help train soldiers to identify aircraft and ships, as well as to estimate range.
Training was always a key use of the View-Master technology, but the company eventually bought a competitor with rights to Disney films and exploded into a must-have toy. When the company was bought by GAF, the focus on the toy market grew. Despite some efforts to keep the company relevant in an era with virtual reality and other 3D technologies, View-Master is, sadly, a bit of nostalgia now, even though you can still buy them. But it is impressive that despite many changes to the viewer and the production methods, the View-Master reel remained virtually unchanged despite the production of about 1.5 billion of them. Sure, there were fancy viewers that had audio tracks, too, but the basic idea of an odd number of film frames mounted in a circle in a notched disk remained the same.
These days, a phone can be your View-Master, at least, if you can cross your eyes. Want to preserve your View-Master reels for posterity? So did [W. Jason Altice].
2026-02-20 00:30:58
Thermoforming is the process of softening a material enough so that it can be tweaked into a new shape, with the source of the thermal energy being not particularly relevant. Correspondingly, after [Zion Brock]’s recent video on his journey into thermoforming PLA with a mold and a heat gun, he got many comments suggesting that he should use hot water instead.
We covered his previous video as well, in which he goes through the design steps of making these grilles for a retro-styled, 3D printed radio. The thermoforming method enables him to shape the curvy grille with a heat gun and two-piece mold in a matter of minutes, rather than spending hours more time printing and removing many supports.
Theoretically using hot water instead of hot air would provide a more equal application of heat, but putting your hands into 70°C water does require some more precautions. There’s also the issue that PLA is very hygroscopic, so the part requires drying afterwards to prevent accelerated hydrolysis. Due to the more even heating, the edge of the PLA that clamped into the mold also softened significantly, causing it to pop out of the mold and requiring a small design modification to prevent this.
Basically, aqua-thermoforming like this has many advantages, as its slower and more consistent, but it’s less straightforward to use than hot air. This makes both a useful tool when you’re looking at doing thermoforming.
2026-02-19 23:00:01
The media is full of breathless reports that AI can now code and human programmers are going to be put out to pasture. We aren’t convinced. In fact, we think the “AI revolution” is just a natural evolution that we’ve seen before. Consider, for example, radios. Early on, if you wanted to have a radio, you had to build it. You may have even had to fabricate some or all of the parts. Even today, winding custom coils for a radio isn’t that unusual.
But radios became more common. You can buy the parts you need. You can even buy entire radios on an IC. You can go to the store and buy a radio that is probably better than anything you’d cobble together yourself. Even with store-bought equipment, tuning a ham radio used to be a technically challenging task. Now, you punch a few numbers in on a keypad.
What this misses, though, is that there’s still a human somewhere in the process. Just not as many. Someone has to design that IC. Someone has to conceive of it to start with. We doubt, say, the ENIAC or EDSAC was hand-wired by its designers. They figured out what they wanted, and an army of technicians probably did the work. Few, if any, of them could have envisoned the machine, but they can build it.
Does that make the designers less? No. If you write your code with a C compiler, should assembly programmers look down on you as inferior? Of course, they probably do, but should they?
If you have ever done any programming for most parts of the government and certain large companies, you probably know that system engineering is extremely important in those environments. An architect or system engineer collects requirements that have very formal meanings. Those requirements are decomposed through several levels. At the end, any competent programmer should be able to write code to meet the requirements. The requirements also provide a good way to test the end product.
A good requirement will look like this: “The system shall…” That means that it must comply with the rest of the sentence. For example, “The system shall process at least 50 records per minute.” This is testable.
Bad requirements might be something like “The system shall process many records per minute.” Or, “The system shall not present numeric errors.” A classic bad example is “The system shall use aesthetically pleasing cabinets.”
The first bad example is too hazy. One person might think “many” is at least 1,000. Someone else might be happy with 50. Requirements shouldn’t be negative since it is difficult to prove a negative. You could rewrite it as “The system shall present errors in a human-readable form that explains the error cause in English.” The last one, of course, is completely subjective.
You usually want to have each requirement handle one thing to simplify testing. So “The system shall present errors in human-readable form that explain the error cause in English and keep a log for at least three days of all errors.” This should be two requirements or, at least, have two parts to it that can be tested separately.
In general, requirements shouldn’t tell you how to do something. “The system shall use a bubble sort,” is probably a poor requirement. However, it should also be feasible. “The system shall detect lifeforms” doesn’t tell you how to make that work, but it is suspicious because it isn’t clear how that could work. “The system shall operate forever with no external power” is calling for a perpetual motion machine, so even if that’s what you wish for, it is still a bad requirement.
You sometimes see sentences with “should” instead of shall. These mark goals, and those are important, but not held to the same standard of rigor. For example, you might have “The system should work for as long as possible in the absence of external power.” That communicates the desire to work with no external power to the level that it is practical. If you actually want it to work at least for a certain period of time, then you are back to a solid and testable requirement, assuming such a time period is feasible.
You can find many NASA requirements documents, like this SRS (software requirements specification), for example. Note the table provides a unique ID for each requirement, a rationale, and notes about testing the requirement.
High-level requirements trace down to lower-level requirements and vice versa. For example, your top-level requirement might be: “The system shall allow underwater research at location X, which is 600 feet underwater.” This might decompose to: “The system shall support 8 researchers,” and “The system shall sustain the crew for up to three months without resupply.”
The next level might levy requirements based on what structure is needed to operate at 600 feet, how much oxygen, fresh water, food, power, and living space are required. Then an even lower level might break that down to even more detail.
Of course, a lower-level document for structures will be different from a lower-level requirement for, say, water management. In general, there will be more lower-level requirements than upper-level ones. But you get the idea. There may be many requirment documents at each level and, in general, the lower you go, the more specific the requirements.
We suspect that if you could leap ahead a decade, a programmer’s life might be more like today’s system architect. Your value isn’t understanding printf or Python decorators. It is in visualizing useful solutions that can actually be done by a computer.
Then you generate requirements. Sure, AI might help improve your requirements, trace them, and catalog them. Eventually, AI can take the requirements and actually write code, or do mechanical design, or whatever. It could even help produce test plans.
The real question is, when can you stop and let the machine take over? If you can simply say “Design an underwater base,” then you would really have something. But the truth is, a human is probably more likely to understand exactly what all the unspoken assumptions are. Of course, an AI, or even a human expert, may ask clarifying questions: “How many people?” or “What’s the maximum depth?” But, in general, we think humans will retain an edge in both making assumptions and making creative design choices for the foreseeable future.
There is more to teaching practical mathematics than drilling multiplication tables into students. You want them to learn how to attack complex problems and develop intuition from the underlying math. Perhaps programming isn’t about writing for loops any more than mathematics is about how to take a square root without a calculator. Sure, you should probably know how things work, but it is secondary to the real tools: creativity, reasoning, intuition, and the ability to pick from a bewildering number of alternatives to get a workable solution.
Our experience is that normal people are terrible about unambiguously expressing what they want a computer to do. In fact, many people don’t even understand what they want the computer to do beyond some fuzzy handwaving goal. It seems unlikely that the CEO of the future will simply tell an AI what it wants and a fully developed system will pop out.
Requirements are just one part of the systems engineering picture, but an important one. MITRE has a good introduction, especially the section on requirements engineering.
What do you think? Is AI coding a fad? The new normal? Or is it just a stepping stone to making human programmers obsolete? Let us know in the comments. Although they have improved, we still think the current crop of AI is around the level of a bad summer intern.
2026-02-19 20:00:21
Getting PCBs made is often the key step in taking a dodgy lab experiment and turning it into a functional piece of equipment. However, it can be tedious to wait for PCBs to ship, and that can really slow down the iterative development process. If you’ve got a 3D printer, though, there’s a neat way to make your own custom PCBs. Enter PCB Forge from [castpixel].
The concept involves producing a base and a companion mold on your 3D printer. You then stick copper tape all over the base part, using the type that comes with conductive adhesive. This allows the construction of a fully conductive copper surface across the whole base. The companion mold is then pressed on top, pushing copper tape into all the recessed traces on the base part. You can then remove the companion mold, quickly sand off any exposed copper, and you’re left with a base with conductive traces that are ready for you to start soldering on parts. No etching, no chemicals, no routing—just 3D printed parts and a bit of copper tape. It rarely gets easier than this.
You can design your PCB traces in any vector editor, and then export a SVG. Upload that into the tool, and it will generate the 3D printable PCB for you, automatically including the right clearances and alignment features to make it a simple press-together job to pump out a basic PCB. It bears noting that you’re probably not going to produce a four-layer FPGA board doing advanced high-speed signal processing using this technique. However, for quickly prototyping something or lacing together a few modules and other components, this could really come in handy.
The work was inspired by a recent technique demonstrated by [QZW Labs], which we featured earlier this year. If you’ve got your own hacks to speed up PCB production time, or simply work around it, we’d love to know on the tipsline!
2026-02-19 17:00:08
Are you ready to feel old? Lemmings just turned thirty-five. The famous puzzle game first came out in February of 1991 for the Commodore Amiga, before eventually being ported to just about everything else out there, from the ZX Spectrum to the FM Towns, and other systems so obscure they don’t have the class to start with two letters, like Macintosh and DOS. [RobSmithDev] decided he needed to commemorate the anniversary with a real floating lemming.
The umbrella-equipped lemming is certainly an iconic aspect of the game franchise, so it’s a good pick for a diorama. Some people would have just bought a figurine and hung it with some string, but that’s not going to get your project on Hackaday. [Rob] designed and 3D printed the whole tableau himself, and designed magnetic levitation system with some lemmings-themed effects.
The mag-lev is of the top-down type, where a magnet in the top of the umbrella is pulled against gravity by an electromagnetic coil. There are kits for this sort of thing, but they didn’t quite work for [Rob] so he rolled his own with an Arduino Nano. That allowed him to include luxuries you don’t always get from AliExpress like a thermal sensors.
Our favorite part of the build, though, has to be the sound effects. When the hall effect sensor detects the lemming statue — or, rather, the magnet in its umbrella — it plays the iconic “Let’s Go!” followed by the game’s sound track. If the figurine falls, or when you remove it, you get the “splat” sound, and if the lemming hits the magnet, it screams. [Rob] posted a demo video if you just want to see it in action, but there’s also a full build video that we’ve embedded below.
A commemorative mag-lev seems to be a theme for [Rob] — we featured his 40th anniversary Amiga lamp last year, but that’s hardly all he gets up to. We have also seen functional replicas, this one of a motion tracker from Aliens, and retrotech deep-dives like when he analyzed the magical-seeming tri-format floppy disk.
2026-02-19 14:00:17
A lot of hacks get inspired by science fiction. When that inspiration is taken from the boob tube or the silver screen, the visual design is largely taken care of by the prop department. If, on the other hand, one seeks inspiration from the written word– like [Math Campbell] did for his smart pocket watch inspired by The Diamond Age— the visuals are much more up to the individual hacker. Though no nanotechnology was involved in its creation, we think [Math] nailed the Victorian High-Tech vibe of [Neil Stephenson]’s cult classic.
The build itself is fairly simple: [Math] started with a Waveshare dev board that got him the 1.75″ round touch display, along with an ESP32-S3 and niceties such as a six-axis IMU, an RTC, microphone, speaker, and micro SD card reader. That’s quite the pocket watch! The current firmware, which is available on GitHub, focuses on the obvious use case of a very stylish watch, as well as weather and tidal display. Aside from the dev board, [Math] needed only to supply a battery and a case.
[Math] designed the case for the watch himself in Fusion360 before sending it off to be 3D printed in stainless steel. That might not be molecular-scale manufacturing like in the book, but it’s still amazing you can just do that. Ironically, [Math] is a silversmith and will be recreating the final version of the watch case in sterling silver by hand. We’d be tempted to include a door–making it a “hunter’s case” in pocket watch lingo–to protect that amoled display, but far be it for us to tell an artist how to do his work. If you’re not a silversmith, [Math] has stated his intent to add STLs to the GitHub repo, though they aren’t yet present at time of writing.
We’ve featured smart pocket watches before, some with more modern aesthetics. Of course a watch doesn’t have to be smart to grace these pages.
Thanks to [Math Campbell] for the tip! If you’ve got time on your hands after ticking done on a project, send us a tip and watch for it to appear here.
