Printing In Three Dimensions, For Real This Time


3D printers don’t continuously print in three dimensions – they print one layer, then another, then another. This is true for every single 3D printing technology, but now Topolabs has a very interesting technique that changes that. They’re printing in three dimensions by moving in the Z axis while also printing in the X and Y axes.

The basic idea behind Topolabs’ software is to print a support block, then print an object right on top of the support. The support block can be curved and convex, and the finished product follows the contours of the solid support block. Unlike ‘printing with supports’, the printer extrudes along the X, Y, and Z axes, which should make the finished product much, much stronger.

There are a few drawbacks to the technique – a release agent must be applied to the top of the support block. In the video below, Topolabs is using Kapton, but hair spray or glue sticks will also work. There’s also a limit to how steep an incline a printer can print, determined by the size of the extruder nozzle. Lastly, this technique would be much better suited for a delta-style bot, but the team is getting very good results with a normal Cartesian bot.

You can see a few videos of the Topolabs printing technique below.

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DIY Linear Actuators For A Flight Sim


[Roland] has already built a few very cool and extremely realistic flight sims, but his latest project will put his current rig to shame. He’s building a six degree of freedom simulator based on homebuilt linear actuators of his own design.

The actuator is powered by a large DC motor moving timing belts along the length of the enclosure. These timing belts are connected to a shaft that’s coupled to the frame with a few bungee cords. The bungee cords are important; without them, the timing belts would be carrying all the load of the sim – not a good thing if these actuators are moving an entire cockpit around a living room.

Also on [Roland]‘s list of awesome stuff he’s building for his flight sims is a vibration system based on the BFF Shaker. This board takes data in from sim software and turns it into vibrations produced by either unbalanced DC motors or one of those ‘bass kicker’ transducers.

It’s all very cool stuff, and with all the crazy upgrades [Roland] is doing to his sim rig, he’s doing much better than paying $300/hour to rent a Beechcraft Baron.

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Using Bitcoin To Detect Malware


Now that you can actually buy things with bitcoins, it’s become a playground for modern malware authors. [Eric] recently lost about 5 BTC because of some malware he installed and decided to do something about it. He came up with BitcoinVigil, a web service that constantly looks at bitcoin honeypots and alerts you when bitcoins are surreptitiously removed.

The idea behind BitcoinVigil is to set up a Bitcoin wallet with a small amount of coins in it – only about $10 USD worth. When modern, Bitcoin-seeking malware is run on a computer, it looks for this ‘moneypot’ and sends an email out notifying the owner of the coins to stolen money.

[Eric] was at a LAN party a few weeks ago and ‘borrowed’ a friend’s copy of Starcraft 1. Just a few seconds after installing it, he received an alert notifying him about a few stolen bitcoins. This time [Eric] only lost a few microBTC, but better than the thousands of USD he lost before.

Fake Audiophile Opamps Revealed


The OPA627 is an old, popular, and very high-end opamp found in gear cherished by the most discerning audiophiles. This chip usually sells for at least $15, but when [Zeptobars] found a few of these expensive chips on ebay going for $2, his curiosity was piqued. Something just isn’t right here.

[Zeptobars] is well known for his decapsulating and high-resolution photography skills, so he cut the can off a real OPA627, and dissolved one of the improbably cheap ebay chips to reveal the die. Under the microscope, he found an amazing piece of engineering in the real chip – laser trimmed resistors, and even a nice bit of die art.

The ebay chip, if it were real, would look the same. It did not. The ebay chip only contained one laser trimmed resistor and looks to be a much simpler circuit. After a bit of research, [Zeptobars] found it was actually an AD774 opamp. The difference is small, but the AD774 still has much higher noise – something audiophiles could easily differentiate with their $300 oxygen-free volume knobs.

This isn’t the first instance of component counterfeiting [Zeptobars] has come across. He’s found fake FTDI chips before, and we’re counting the days until he gets around to putting a few obviously fake ebay 6581 SID chips under the microscope.

An Exceptional BASIC Computer


Since [Dan] has started using microcontrollers, he’s been absolutely fascinated by the fact these chips are essentially low performance computers. Once he caught wind of TinyBASIC, he decided he would have a go at creating a simple, tiny computer that’s very simple to the old, tiny, 8-bit computers of yore.

The computer is built on an Arduino shield, using TinyBASIC, the TVout library, and the PS/2 keyboard library. After piecing together a little bit of code, the Arduino IDE alerted [Dan] to the fact the TVout and PS/2 libraries were incompatible with each other. This inspired [Dan] to use the ATMega328P as a coprocessor running the TVout library, and using the capacious ATMega1284P as the home of TinyBASIC and the PS/2 library.

A circuit was put together in Fritzing using minimal components, and a PCB milled out of copper board. After the board was tinned, [Dan] had a beautiful minimalist retro computer with nearly 14kB of RAM free and an RCA display.

Future versions of the build will probably be based around the Arduino Mega, allowing for a TV resolution of 720×480. Also on tap are an SD card slot, LEDs, pots, and possibly even headers for I2C and SPI.

Resetting DRM On 3D Printer Filament


The Da Vinci 3D printer is, without a doubt, the future of printing plastic objects at home. It’s small, looks good on a desk, is fairly cheap, and most importantly for printer manufacturers, uses chipped filament cartridges that can’t be refilled.

[Oliver] over at Voltivo was trying to test their new printer filament with a Da Vinci and ran head-on into this problem of chipped filament. Digging around inside the filament cartridge, he found a measly 300 grams of filament and a small PCB with a Microchip 11LC010 EEPROM. This one kilobyte EEPROM contains all the data about what’s in the filament cartridge, including the length of filament remaining.

After dumping the EEPROM with an Arduino and looking at the hex file, [Oliver] discovered the amount of filament remaining was held in a single two-byte value. Resetting this value to 0xFFFF restores the filament counter to its virgin state, allowing him to refill the filament. A good thing, too; the cartridge filament is about twice as expensive as what we would normally buy.


Turning An Analog Scope Into A Logic Analyzer


When [Marco] was planning on a storage oscilloscope build, he realized having a small device to display eight digital signals on an analog scope would be extremely useful. This just happens to be the exact description of a simple logic analyzer and managed to turn his idea into a neat little project (German, Google translation).

The theory of operation for this surprisingly simple, and something that could be completed in a few hours with a reasonably well stocked hackerspace or parts drawer in a few hours. A clock generator and binary counter are fed into the lower three bits of a simple R2R DAC, while the 8 inputs are fed into an 8-input multiplexer and sent to the last bit of the DAC. With nothing connected to the logic analyzer inputs, the output to the scope would just be an 8-step ramp that would appear as eight horizontal lines on the screen. With something connected to the logic analyzer input, an extremely primitive but still very useful logic analyzer appears on the screen.

While it’s not the greatest analyzer, it is something that can be cobbled together in an hour or two, and the capabilities are more than sufficient to debug a few simple circuits or figure out some timings in a project.