Four times the holes, four times the trouble. With the fate of repetitive motion injury looming due to the need to drill 1,200 holes, [bitluni] took matters into his own hands and built this nifty DIY hole punch for light-gauge sheet metal.
A little backstory will probably help understand why [bitluni] needs so many holes. Back in May, he built a ping pong ball LED video wall for Maker Faire Berlin. That had 300 LEDs and came out great, but at the cost of manually drilling 300 holes in sheet steel with a hand drill. Looking to expand his wall of balls to four times the original size, [bitluni] chose to spend a few days building a punch to make the job more appealing. The business end, with solid bar stock nested inside pieces of tubing, is a great example of how much you can get done without a lathe. The tool is quite complex, with a spring-loaded pilot to help guide the punching operation. When that proved impractical, [bitluni] changed the tool design and added an internal LED to project crosshairs from inside the tool.
The tool itself is mounted into a sturdy welded steel frame that allows him to cover the whole aluminum sheet that will form the panel of his LED wall. It’s pretty impressive metalwork, especially considering this isn’t exactly in his wheelhouse. And best of all, it works – nice, clean holes with no deformation, and it’s fast, too. We’re looking forward to seeing the mega-LED wall when it’s done.
There are truisms about dice that you’ve probably already heard: if you have just one of them it’s called a “die”, opposite faces of each die always add up to seven, and those dots that you’re adding together are known as “pips”. But what about the infrared properties of those pips? It turns out they reflect less IR than the white body of the die and that trait can be used to build an automatic die reader.
Great projects have a way of bubbling to the surface. The proof of concept comes from way back in 2009, and while the source blog is now defunct, it’s thankfully been preserved by the Internet Archive. In recreating the project based on that barebones description, [Calvin] reached for a set of five IR transmitter/receiver pairs. Take a close look and you’ll see each transmitter is hidden under its partnered receiver. The light shines up through the receiver and the presence of the pip is detected by measuring how much of it bounces back.
This board is only the sensor portion of the design. A 595 shift register provides the ability to control which IR pair is powered, plus five more signals heading out to the analog pins of an Arduino Uno to monitor how much light is being detected by the receivers. Hey, that’s another interesting fact about dice, you only need to read five different pips to establish the value shown!
People take their tabletop games very, very seriously. [Andrew Lauritzen], though, has gone far above and beyond in pursuit of a fair game. The game in question is Star War: X-Wing, a strategy wargame where miniature pieces are moved according to rolls of the dice. [Andrew] suspected that commercially available dice were skewing the game, and the automated machine-vision dice tester shown in the video after the break was the result.
The rig is a very clever design that maximizes the data set with as little motion as possible. The test chamber is a box with clear ends that can be flipped end-for-end by a motor; walls separate the chamber into four channels to test multiple dice on each throw, and baffles within the channels assure randomization. A webcam is positioned below the chamber to take a snapshot of each “throw”, which is then analyzed in OpenCV. This scheme has the unfortunate effect of looking at the dice from the table’s perspective, but [Andrew] dealt with that in true hacker fashion: he ignored it since it didn’t impact the statistics he was interested in.
And speaking of statistics, he generated a LOT of them. The 62-page report of results from his study is an impressive piece of work, which basically concludes that the dice aren’t fair due to manufacturing variability, and that players could use this fact to cheat. He recommends pooled sets of dice to eliminate advantages during competitive play.
This isn’t the first automated dice roller we’ve seen around these parts. There was the tweeting dice-bot, the Dice-O-Matic, and all manner of electronic dice throwers. This one goes the extra mile to keep things fair, and we appreciate that.
While it’s arguably a bit closer to the “Arts & Crafts” region of the making spectrum upon which we don’t usually tread on account our l33t sense of superiority, we’ve got to admit that the quick and easy notebook customization demonstrated by [Sean Hodgins] is very compelling. We don’t put ink to dead trees with nearly the frequency we used to, but when we do it might as well be Hemingway-style with a little black Hackaday emblazoned notebook.
As demonstrated in the video after the break, the process starts by designing the stamp in your CAD package of choice. For optimal results [Sean] suggests fairly large capital letters, but with practice you should be able to get into some more creative fonts. Potentially you could even use the logo of your favorite hacking blog, but who are we to dictate what you do?
Whatever you chose, it needs to be mirrored and placed on a relatively thick backing. He recommends a 2 mm thick “plate” with the letters raised on top. You’ll want to print it at a high infill percentage, but even still it shouldn’t take more than 30 minutes or so to run off. Remember there tends to be diminishing returns on infill past 50%, so taking it all the way to 100% is not going to do much but expend more time and plastic.
Once printed, [Sean] hot glues the stamp to a block of wood since putting pressure on the printed piece directly would likely crack it. Then it’s just a matter of getting your notebook, printed stamp, and blocks of wood lined up in to a suitably beefy bench vise. Getting everything aligned is one of those things that easier said than done, so expect to mess up the first couple until you get the hang of it.
When the alignment looks good, crank it down and let it sit for a few minutes. If you’re embossing the design into actual leather, wetting it a bit before putting the pressure on should help. The final effect is understated but undeniably very slick; and with the Holidays rapidly approaching this might be an excellent way to knock out some legitimately thoughtful gifts.
For most of human history, our inventions and innovations have been at a scale that’s literally easy to grasp. From the largest cathedral to the finest pocket watch, everything that went into our constructions has been something we could see with our own eyes and manipulate with our hands. But in the middle of the 20th century, we started making really, really small stuff: semiconductors. For the first time, we were able to create mechanisms too small to be seen with the naked eye, and too fine to handle with our comparatively huge hands. We needed a way to scale these devices up somewhat to make them useful parts. In short, they needed to be packaged.
We know that the first commercially important integrated circuits were packaged in the now-familiar dual in-line package (DIP), the little black plastic millipedes that would crawl across circuit boards for the next 50 years. As useful and versatile as the DIP was, and for as successful as the package became, its design was anything but obvious. Let’s take a look at the dual in-line package and how it got that way.
In the closing months of World War II, the Axis and the Allies were throwing everything they had at each other. The tide was turning to the Allies’ favor, but the Germans were showing a surprising resilience, at least in terms of replacing downed fighter and bomber aircraft. When the Allies examined the wreckage of these planes, they discovered the disturbing truth: the planes contained large pieces forged from single billets of metal, which suggested a manufacturing capability none of the Allies possessed and which allowed the Germans to quickly and cheaply make better and faster planes.
When the war was over, the Allies went looking for the tools the Germans had used to make their planes, and found massive closed-die forging presses that could squeeze parts out of aluminum and magnesium alloys in a single step. The Soviets carted off a 30,000 ton machine, while the Americans went home with a shipload of smaller presses and the knowledge that the Russians had an edge over them. Thus began the Heavy Press Program, an ultimately successful attempt by the US military to close a huge gap in strategic manufacturing capabilities that [Machine Thinking] details in the excellent video below.
One doesn’t instantly equate monstrous machines such as the Mesta 50,000-ton press, over nine stories tall with half of it buried underground and attached directly to bedrock, with airplane manufacture. But without it and similar machines that came from the program, planes from the B-52 to the Boeing 747 would have been impossible to build. And this isn’t dead technology by any means; sold to Alcoa in 1982 after having been operated by them for decades, the “Fifty” recently got a $100 makeover after cracks appeared in some castings, and the press and its retro-brethren are still squeezing out parts for fighters as recent as the F-35.
It’s easy to assume that older components will be less integrated and bulkier than we might otherwise expect. Then something seems ahead of its time, like the teeny-tiny 490IP1 LED which was produced in the former Soviet Union. [AnubisTTP] obtained and shared images of this tiny integrated single digit LED display in which the number measures a scant 2.5 mm tall; in production it was made easier to read with an external bubble lens magnifier clipped to the outside. The red brick the 490IP1 is pictured with is the Texas Instruments TIL306, a relatively normal sized DIP component with similar functionality.
The 490IP1 is called an intelligent LED display because the package contains a decade counter and driver circuitry for the integrated seven-segment LED digit, complete with a carry signal that meant multiple displays could be chained together. It is notable not just due to its size, but because the glass cover makes it easy to see the die inside, as well as the wire-bonded pads.
It’s always fascinating to see glimpses of the development path that display technologies took. It’s easy to take a lot of it for granted today, but back before technology was where it is now, all sorts of things were tried. Examples we’ve seen in the past include the fantastic (and enormous) Eidophor projector which worked by drawing images onto a rotating disk of oil with an electron gun. On the smaller end of things, the Sphericular display used optics and image masks to wring a compact 0-9 numerical display out of only a few lamps at the back of a box.