There’s nothing wrong with the rough experiments like hanging a 1 L bottle of water from the end of a rectangular test print to compare strengths. We also have our rules-of-thumb, like expecting the print to perform at 30% of injection molded strength. But these experiments are primitive and the guidelines are based on hearsay. Like early metallurgy or engineering; 3D printing is full of made-up stuff.
What [Sam] has done here is really amazing. He’s produced a model of a printed ABS part and experimentally verified it to behave close enough to the real thing. He’s also set a method for testing and proposed a new set of questions. If it couldn’t be better, he also included his full research notebook. Make sure to read the FDMProperties-report (PDF) in the files section of Hackaday.io.
If research like this is being done elsewhere, it’s either internal to a large 3D printer manufacturer, or it’s behind a paywall so thorough only the Russians can help a regular peasant get through to them. Anyone with access to a materials testing lab can continue the work (looking at you every single engineering student who reads this site) and begin to help everyone achieve an understanding of 3D printed parts that could lead to some really cool stuff one day.
Inside the second edition of the Hackaday Omnibus is 128 pages of actual, real content. There are zero ads, no sponsored content, and absolutely nothing that tells you to go out and buy something. Opening it is an experience unlike anything. Where can you read something for minutes at a time with no interruptions, no email, no Twitter, no Facebook, no text messages, and no ads? You won’t find something like this anywhere else.
The electronics, trade, and tech magazines have a long and storied history. In the 1930s, there were magazines that would teach you how to build a radio. In the 1950s, there were print articles saying fusion power was just fifty years away. The Hackaday Omnibus continues this tradition with relevant content for today: everything from car hacking and open source insulin, to retrospectives on oft-forgotten parts of our digital heritage are included. This is the best we have to offer, and we’re doing it without selling out.
Volume Two of the Hackaday Omnibus isn’t the end for our print endeavours – we’re just getting started. We’re committed to producing the best content in an interruption-free format. Print is dead, after all, and that’s why we put a skull on it.
You can purchase the Hackaday Omnibus Volume Two on the Hackaday Store.
It’s no secret that a great deal of Western civilization was informed by the ancient Greeks. They revolutionized mathematics and geometry, developing astronomy along the way. They built ornate statues, beautiful temples to the gods, and amphitheaters for live entertainment with astonishing acoustics. The influence of the ancient Greeks shaped almost every field of human knowledge, from the arts and architecture to politics, philosophy, science, and technology.
Like the Babylonians, the Greeks paid close attention to the night sky. Our nearest celestial neighbor, the Moon, was particularly important to them from a planning perspective. For instance, debts might be due on the new Moon. By heeding the Moon’s phases and taking note of eclipse cycles, they found that their harvests were more fruitful, and they had fewer incidents at sea.
As savvy and well-rounded as ancient Hellenistic culture appears to have been, it’s not unreasonable to imagine that the Greeks could have created some kind of computing machine to make their Moon-centered scheduling easier. Based on fragments from in a shipwreck that was discovered in 1900, it seems they did exactly this. Based on scientific dating of the coins and pottery found in the wreck and inscriptions on the bronze remnants, historians and scientists believe the Greeks created a mechanical computer capable of calculating the positions of the Sun and the Moon on any given day. This marvelous device is known as the Antikythera mechanism.
The mechanism was housed in a wooden box and controlled with a knob on one side. It is believed that the front of the box was a display made up of a set of concentric rings with graduations, and that each ring corresponded with one celestial body. Pointers attached perpendicularly to output gears moved around the rings as the knob was turned, showing the paths and positions of these celestial bodies over time. This Earth-centric planetarium also displayed the phase of the Moon as well as the positions of the five major planets known to the ancient Greeks—Mercury, Venus, Mars, Jupiter, and Saturn.
Now is your chance to hold a piece of Hackaday in your hands. Last year we announced our first ever print edition. We continue that tradition with a much bigger offering. Hackaday Omnibus vol #02 gathers the best content from Hackaday over the last year. This includes in-depth original content, incredible art, the events that mattered over the last 12 months, and a few cryptic easter eggs.
[Joe Kim], Hackaday’s Art Direct, really outdid himself with the cover this year. Inspired by an epic movie, the illustration includes a shoutout to almost every article found within. Of course there is a lot more of his work inside, along with the efforts of dozens of writers, artists, editors, and more.
All 128 pages of Omnibus vol #02 were painstakingly laid out by [Aleksandar Bradic] who enlisted the help of a dedicated core of Hackaday.io members to help pore over the final drafts, ensuring the presentation is immaculate. Along the way some of them teamed up to roll in those easter eggs that I previously mentioned. We don’t even know what all of it means, you should be the first to solve the mystery.
Most of the 31 articles that grace these pages have run past the front page of Hackaday. But there are a few that were written specifically for the print edition. These will be published on our front page starting in 90 minutes and continuing for a few weeks. It is important to us to share these great works without the need to purchase anything. But the Omnibus is truly one of the coolest pieces of tech literature that you can own. It deserves a place on your coffee table, reception area at work, and as a gift for all who love to know how things work, how things were built, and the legacy of knowledge that has come from generations of hacking.
We’re only running a single printing of this gorgeous volume. Make sure you get one of your own by placing a pre-order now. Be one of the first 500 using coupon code OMNIBUS2015 and get it for just $10! Show that you support great content and help make future projects like this possible.
The folks over at Lunchbox Electronics are working on a very cool prototype: embedding LEDs inside standard 1×1 Lego bricks. Being a prototype, they needed a cheap way to produce Lego bricks stuffed with electronics. It turns out a normal 3D printer has okay-enough resolution, but how to put the electronics in the bricks? Gcode wizardry, of course.
The electronics being stuffed into the bricks isn’t much – just a small PCB with an LED. It does, however, need to get inside the brick. This requires stopping the 3D printer at the right layer, moving the print head out of the way, inserting the PCB, and moving the head back to where it stopped.
Gcode to the rescue. By inserting a few lines into the Gcode of the print, the print can be paused, the print head raised and returned, and the print continued.
[Helios Labs] recently published version two of their 3D printed fish feeder. The system is designed to feed their fish twice a day. The design consists of nine separate STL files and can be mounted to a planter hanging above a fish tank in an aquaponics system. It probably wouldn’t take much to modify the design to work with a regular fish tank, though.
The system is very simple. The unit is primarily a box, or hopper, that holds the fish food. Towards the bottom is a 3D printed auger. The auger is super glued to the gear of a servo. The 9g servo is small and comes with internal limiters that only allow it to rotate about 180 degrees. The servo must be opened up and the limiters must be removed in order to enable a full 360 degree rotation. The servo is controlled by an Arduino, which can be mounted directly to the 3D printed case. The auger is designed in such a way as to prevent the fish food from accidentally entering the electronics compartment.
You might think that this project would use a real-time clock chip, or possibly interface with a computer to keep the time. Instead, the code simply feeds the fish one time as soon as it’s plugged in. Then it uses the “delay” function in order to wait a set period of time before feeding the fish a second time. In the example code this is set to 28,800,000 milliseconds, or eight hours. After feeding the fish a second time, the delay function is called again in order to wait until the original starting time.
February 9th has come and gone and the Hackaday Omnibus 2014 is now shipping. If you were one of the early adopters who pre-ordered, thank you very much it should be in your hands shortly! If you missed out on the Pre-Order, don’t worry you can still get a copy of your very own but we only ordered a small over-run so don’t wait too long.
The Omnibus celebrates the best our writers and illustrators published in 2014 with an 80-page full color volume printed on premium paper. From tales of technology past, to current events, the Omnibus tells the story of what the high points in hardware were last year. We have fallen in love with having a physical version of this content since the proof copies hit our hands a month ago. We believe that this is a conversation waiting to happen — set it out and watch your friends gravitate toward it.
We’ve already seen them popping up on Twitter and we’d love to see more. Make sure to Tweet a picture of your copy to @Hackaday with hashtag #hadOmnibus. We’re happy to see any pictures shared, but if you’re one of the lucky souls who works with awesome hardware make sure to take some ‘extreme’ shots. For instance, reading while you wait for the cyclotron to warm up, the nuclear sub to surface, or your ride to pick you up from Amundsen-Scott.
This is our first ever print edition and we’ve gone to great lengths to make sure it’s something you’ll be proud to have on your coffee table, bookshelf, or anywhere for years to come.