Hackaday Links: August 18, 2013

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Let’s start off with some lock picking. Can you be prosecuted if it was your bird that broke into something? Here’s video of a Cockatoo breaking into a puzzle box as part of an Oxford University study. [Thanks Ferdinand via Endandit]

[Augybendogy] needed a vacuum pump. He headed off to his local TechShop and machined a fitting for his air compressor. It uses the Venturi Effect to generate a vacuum.

Build your own Arduino cluster using this shield designed by [Bertus Kruger]. Each shield has its own ATmega328. Many can be stacked on top of an Arduino board, using I2C for communications.

[Bunnie Huang] has been publishing articles a few articles on Medium called “Exit Reviews”. As a treasured piece of personal electronics is retired he pulls it apart to see what kind of abuse it stood up to over its life. We found his recent article on his Galaxy S II quite interesting. There’s chips in the glass, scuffs on the bezel, cracks on the case, and pervasive gunk on the internals.

We’d love to see how this this paper airplane folder and launcher is put together. If you know of a post that shares more details please let us know.

Squeezing the most out of a tiny microcontroller was a challenge. But [Jacques] reports that he managed to get a PIC 10F322 to play a game of Pong (translated). It even generates an NTSC composite video signal! Watch the demo video here.

Fail Of The Week: The Follies Of A Bootstrapped CNC Mill

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Anyone who’s built their own CNC machine from scratch will tell you that it’s no walk in the park. Heck, even commercially available (but hobby priced) 3D printers are no picnic to get running reliably. This offering is the tale of how [Brian Amos] failed at building a CNC mill over and over again. But hey, that ‘over and over again’ part is what makes great hackers. He not only documented what didn’t work, but shows the hacks that he tried using to work through each scrape.

We think the most interesting bits are in his second post, but start with the first one (it’s a quick read) to get the background on the project. The real issues start with a common one: a bed that is severely unlevel compared to the cutting head’s axes. The solution is to use a sacrificial bed, milling it out to match the surface to the tool. This exposed the next issue which is a misaligned Z axis. Some give in the entire support structure means problems with slop and backlash. And there’s even a very creative spiral-cut coupler to help account for alignment issues between the lead screws and motors.

The nice thing about building a mill is that you can turn around a use it to mill more accurate replacement parts. Just keep telling yourself that as you toil away at a project that just won’t seem to work!

We’re already looking for next week’s fail post topic. Help keep the fun rolling by writing about your past failures and sending us a link to the story.

3D Printering: Where Can I Get The Cheapest Filament?

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We’ve complained about the price of 3D printing filament, and cheered at the machine that makes filament out of plastic pellets. Still, the price of filament for our 3D printers is climbing ever higher, leaving us to wonder, where can I get the cheapest filament?

Now, I’m going to start this of by saying this is a work in progress. Canvassing suppliers on every continent for 1.75 and 3mm ABS and PLA for every possible color while accounting for different amounts of filament and shipping is a whole lot of work. Therefore, we’re going to do this in parts, first starting with how much it will cost me to get a kilogram of PLA shipped to my door. This should be a valid test for just about everyone in the USA.

The test criteria is simple: find a supplier of PLA on the Reprap wiki printing material suppliers page and figure out how much it would cost me to get 1 kg of white or natural PLA shipped to my front door. I’ve organized this in a spreadsheet (below) that contains the supplier, size (1.75 mm or 3mm), weight (usually 1 kg although some suppliers are about three ounces short), color, and price with shipping included.

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Retrotechtacular: Understanding A Voltage Doubler

This very stern looking gentleman is about to explain how voltage doubles work in a plodding, yet satisfyingly thorough manner.

We’re not certain when this US Air Training Command video was produced. Obviously it was used to train servicemen who were responsible for keeping electronics running during war time. We’re glad for that, as they really found just the right balance to present a concept that required some knowledge, but is approachable for even the most basic of new electronics hackers.

The demonstration board shown on the right is the voltage circuit highlighted in the lesson. Here the pointing stick is being used to trace out the circuit function during one phase of the input transformer. The capacitor/diode pairs rectify the voltage, with the capacitors discharging in parallel series to double the output voltage. But how does the variable load (RL) affect the output? This is demonstrated under several different conditions using an oscilloscope to illustrate the change.

The discussion of how the diodes work reminded us of a modern tutorial we just ran across this weekend. It’s a bit bizarre, but explains the PN junction in a different way than we’re accustomed to. In this case you will already need to be familiar with how semiconductors work to understand the presentation.

Both clips can be found below the jump.

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Hackaday Links: August 11, 2013

While we’re not much for fashion hacks, we’re reasonably impressed with [Karolina]’s faux Chanel bag made of chips. Apparently a grid of black squares is one of Chanel’s trademark looks, and a thousand or so QFP chips makes for a reasonable substitution.

News of the death of our retro edition has been greatly exaggerated. [Brandon] got an old Apple IIe up on the Internet and loaded up our retro edition, so we’re sort of obliged to mention him. He’s using a Super Serial Card connected to an OS X box running lynx. With getty running, he can shoot the output of lynx over to the Apple. Awesome.

Take an old Yamaha organ, convert the keyboard to MIDI, throw in a few Arduinos, thousands of LEDs, and a handful of bubble machines. What you end up with is the bubble organ, as seen at the Bass Coast Festival last weekend. If you want a hands on, you can also check it out at the Rifflandia festival in BC, Canada this September.

Some guy over on reddit created the smallest Arduino in the world. We’re looking at a rank amateur here, though. I’ve been working on this little guy for the last 18 months and have even created an open source cloud based github design for the production model. It’s less than half the size of a Digispark, and also Internet of Things 3D interactive education buzzword buzzword.

[Moogle] found an old Super 8 camera at an estate sale. No big deal right? Well, this one is clear, and it uses light-sensitive film. Your guess is as good as ours on this one, but if you know what’s up, drop a note in the comments.

One day [John] decided he would put a PC inside an old G3 iMac. After a year, it’s finally done. He took out the CRT and replaced it with a 15″ Dell monitor. The G3 was discarded for an AMD, and the internal speakers and slot-load CD drive still work. It’s a really, really cool piece of work.

Fail Of The Week: Inaugural Edition

We’re sure you’ve all been waiting on the edge of your seats to see whose project makes it as the first Hackaday Fail of the Week. Wait no longer, it’s [Mobile Will] with his woeful tale about monitoring AC current usage.

He had been working on a microcontroller actuated mains outlet project and wanted an accurate way to measure the AC current being used by the device connected to it. The ADE7753 energy metering IC was perfect for this so he designed the board above and ordered it up from OSH Park. After populating the components he hooked it up to his Arduino for a test run, and poof! Magic blue smoke arose from the board. As you’ve probably guessed — this also fried the Arduino, actually melting the plastic housing of the jumper wire that carried the rampant current. Thanks to the designers of the USB portion of his motherboard he didn’t lose the computer to as the current protection kicked in, requiring a reboot to reset it.

We can’t wait to hear the conversation in the comments. But as this is our first FotW post we’d like to remind you: [Mobile Will] already knows he screwed up, so no ripping on his skills or other non-productive dibble. Let’s keep this conversation productive, like what caused this? He still isn’t completely sure and that would be useful information for designing future iterations. Update: here’s the schematic and board artwork.

We’ve got a bit more to share in this post so keep reading after the break.

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3D Printering: Remote Control Of 3D Printers

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With new owners comes new editorial direction. You’re looking at the first evidence of that right now. We’re going to be doing some weekly columns dedicated to certain subjects, and with our fascination of all things three dimensional, it only made sense our first weekly column was dedicated to 3D printers. And using 3D printers, stuff made with 3D printers. Also, things that can be used with 3D printers. Great wordsmiths we are, we’re calling this column ‘3D Printering.’ If you have a better name (or a title pic) send it in and we’ll probably use it.

With that out of the way…

This week we’re taking a look at remote printing. With anything from an Android tablet to a Raspberry Pi, it’s possible to have a networked 3D printer, the perfect thing for hackerspaces or anyone who wants to print objects from multiple computers. One of the most-used tools for this is OctoPrint, a printer host designed to be run on small embedded devices such as a Raspi.

We’ve seen OctoPrint before. but since then it’s matured a whole lot. with a ton of reports of successes running on everything from a Raspberry Pi, BeagleBone Black, and even an OUYA. All the major electronics boards – RAMPS, RAMBo, Sanguinololu – and firmwares should work with OctoPrint, making an Internet-connected 3D printer simply a matter of connecting a Raspberry Pi.

Of course OctoPrint isn’t the only networking solution for a 3D printer. PrintToPeer is deep into development and should be released sometime this fall. It’s a much more sophisticated way of networking a printer that includes an iPad app and ‘enterprise class’ functionality.

The PrintToPeer team is offering private beta invitations, but with a catch: you need to print out a piece of a sculpture and send it to them. These pieces will be unveiled in September as the largest 3D printed sculpture, and the word’s first collaborative 3D sculpture.