Hack a Day

If you’ve ever used an extruding 3D printer, you know that the resulting prints aren’t exactly smooth. At the Southackton hackerspace [James] and [Bracken] worked out a method of smoothing the parts out using vapor. The method involves heating acetone until it forms a vapor, then exposing ABS parts to the vapor. The method only works with ABS, but creates some good looking results.

Acetone is rather flammable, so the guys started out with some safety testing. This involved getting a good air to fuel mixture of acetone, and testing what the worst case scenario would be if it were to ignite. The tests showed that the amount of acetone they used would be rather safe, even if it caught fire, which was a concern several people mentioned last time we saw the method.

After the break, [James] and [Bracken] give a detailed explanation of the process.

Filed under: 3d Printer hacks, chemistry hacks

Ah R2D2. Probably one of the most recognized little robots on the planet. There have to be a hundred different toys of R2 out there, but one of the more impressive is the 30th Anniversary Interactive edition. Complete with all kinds of bells and whistles, it’s about as realistic as they come. One Star Wars fan found himself in possession of a broken Interactive R2, and with his girlfriend’s birthday coming up, decided to do a little droid surgery to create the ultimate gift.

Giving Anakin a run for his money, all the controls for this R2 unit were custom built.  A Raspberry Pi running Rasbian acts as the brain. Facial recognition was implemented using OpenCV. Voice commands in either English or Chinese were made possible by PocketSphinx. Some of the other features he included are: message recording and playback, ultrasonic distance detection, motion detection, wifi, and a rechargeable battery. Many of those features were included in the original toy, but since this unit was broken, had to be rebuilt from scratch.

In the end, it must have impressed his girlfriend – she’s now his wife. Good work Jedi. Check out some build photos and a video demonstration after the break.

Filed under: Raspberry Pi, robots hacks, toy hacks

We agree with [Zapmaker] that Canon cameras chew through nickel metal hydride batteries. But we’re not going to use Alkaline because we think it’s wasteful. His solution is to use a battery that has a higher voltage rating. What you see here is a single lithium iron phosphate cell paired with a dummy cell to increase life between charges.

The reason that NiMH batteries don’t last very long is that they’re only rated at 2.4V. It won’t take long for that voltage to drop below the camera’s cutoff threshold since they didn’t start very high to begin with. But a single LiFePO4 cell has the same form-factor but produces 3.2V and maintains voltage well through it’s discharge cycle.

The size is right, but using one cell won’t work by itself. He built a filler for the other slot which is just a wood dowel with a screw all the way through it. The point was ground down and a bit of foil added to ensure a proper connection. We’d be interested to hear back about how this performs over the long term.

Filed under: green hacks

Odds are you played the game of Operation when you were a kid. The classic electronic toy challenges you to use a tethered tweezers to extract plastic pieces without touching the sides of the holes they’re hiding in. This upgrade makes the challenge more interesting for a grown-up audience. If you touch the sides you won’t hear a jarring sound, you’ll get a painful shock!

The modification starts by clipping off the melted plastic portions that hold the paperboard face plate on the game. From there the original electronics are completely removed. We think this a bit of a mistake as we’d still like spectators to hear the sound as the player gets a shock. But we digress. The circuit board from a disposable camera is patched into the game. A wrist band forms an electrical connection with your body, providing a path for the camera’s flash capacitor to discharge if you happen to touch the sides with the tweezers.

This write-up is missing one important thing: video of someone getting shocked. [Psycosisnine] promises to add some soon, but for now you’ll just have to fall back on our absolute favorite Mindflex shock project.

Filed under: High Voltage Hacks

We consider ourselves fairly cautions Internet warriors. We know when to watch out for malicious links and tread lightly during those times. But this hack will still bite even the most cautions of link followers. It’s a hack that changes where a link is sending you after you click on it.

The concept is driven home right away by a link in the post which lists PayPal as the target when you hover over it with your mouse. Clicking on it will give you a warning that it could have been a malicious page you were redirected to. Of course the address line of the page shows that you were sent somewhere else, but it’s still an interesting issue. The hack is accomplished with just a few lines of JavaScript. In fact, the original example was 100 characters but a revision boils that down to just 67.

So who’s vulnerable to this kind of thing? It sounds like everyone that’s not using the Opera browser, which has been patched against the exploit. There are also some updates at the bottom of the post which mention that Firefox has been notified about it and Chrome is working on a patch.

[via Reddit]

Filed under: security hacks

The form factor of this keyboard just doesn’t look right. What’s missing? Oh, the numpad has been completely removed! We use our numpad almost exclusively (especially when coding) so it’s a little hard to figure out why [Ludw] did this. His only mention of motive is that he wanted the mouse closer to the main part of the keyboard and that he didn’t use the numpad. No matter what the reason, we still think he did an amazing job of giving new life to the older keyboard.

It started out as a plain old beige Cherry G80-3000 keyboard. After cracking open the case [Ludw] carefully traced out the connections between the key matrix and the PCB which provides the USB connection. This is because the controller is mounted over on the part of the PCB he his about to remove. Before making the cuts he desoldered all seventeen switches (these can be reused to fabricate a new keyboard, or add switches to various projects). He then lopped off the depopulated substrate and used point-to-point soldering to reconnect the controller. A bit of case alteration removed the extra space while also reusing the nicely molded edges. A clean and tidy paint job finishes the hack.

[via Reddit]

Filed under: peripherals hacks

[Angus Gratton] recently cracked open a pair of USB to Ethernet converters to see what’s inside. One was an Apple branded device, the other a no-name from eBay. The former rings in at $30, with the latter just $4. This type of comparison is one of our favorites. It’s especially interesting with Apple products as they are known for solid hardware choices and the knock-offs are equally infamous for shoddy imitations.

From the outside both devices look about the same. The internal differences start right away with a whole-board metal shield on the Apple dongle and none on the off-brand. But the hardware inside is actually quite similar. There’s an RJ-45 jack on the left, followed by the Ethernet isolation chip next to it. From there we start to see differences. The off-brand had a blank chip where Apple’s ASIX AX88772ALF USB to Ethernet bridge controller is located. There is also a difference with the clock; Apple is using two crystals with the other using just one.

[via Reddit]

Filed under: teardown

[Chris Osborn] had an old Atari 800 collecting dust and decided to pull it out and get to work. The problem is that it’s seen some rough storage conditions over the years including what appears to be moisture damage. He’s read about a cartridge called SALT II which can run automatic diagnostics. Getting your hands on that original hardware can be almost impossible, but if he had a flashable cartridge he could just download an image. So he bought the cheapest cartridge he could find and modified it to use an EPROM.

When he cracked open his new purchase he was greeted with the what you see on the left. It’s a PCB with the edge connector and two 24-pin sockets. These are designed to take 4k ROMs. He dropped in an EPROM of the same size but the pin-out doesn’t match what the board layout had in mind. After following the traces he found that it is pretty much an exact match for an Intel 2764 chip. The one problem being that the chip has 28-pins, four too many for the footprint. The interesting thing is that the larger footprint (compared to the 2732) uses all the same pins, simply adding to the top and moving the power pins. A small amount of jumper wire soldering and [Chris] is in business.

Filed under: classic hacks

When playing around with a cheap, handheld, dual-band radio, [Lior], a.k.a. [KK6BWA], found a schematic for a similar and even cheaper radio. He realized the programming pads were very accessible and the dev tools for the radio’s microcontroller were available from the manufacturer. After these discoveries, there really was only one thing to do: write new firmware for a $40 radio, and making a great tool for playing around in the 2 meter and 70 cm bands.

The instructions for reflashing the firmware on this radio only require an Arduino and a handful of miscellaneous components. [Lior]‘s new firmware for the uv3r radio isn’t quite finished yet, but he plans on adding some really impressive features. Things like a better UI for a four-button radio, a mode for tracking satellites, a digital mode, and a computer-controlled mode are all possible and on [Lior]‘s project wishlist.

Getting a $40 radio to do your bidding with an Arduino is cool enough, but [Lior] says this mod for the uv3r can be taken even further: if you’ve got an amateur radio license, it’s possible to use the uv3r to control an Arduino or other microcontroller from miles away. It’s a great hack, right up there with the USB TV tuner/software defined radio thing we saw almost exactly one year ago.

You can check out a demo of some custom software running on the uv3r after the break. The radio listens for a DTMF tone (supplied by the uv3r’s big brother, the uv5r), and plays back a three-digit DTMF tone. There’s also a more through walk through of what [Lior]‘s new radio can do as well.

Filed under: radio hacks

LulzBot, the awesomely named 3D printer manufacturer and parts supplier, is giving away eight of their AO-100 printers to eight lucky hackerspaces.

It’s not so much a contest, but instead a giveaway aimed at eight community-operated hackerspaces who come up with a great idea on how to use a 3D printer. If you’re part of a well-established hackerspace that doesn’t have a 3D printer yet, this is a great opportunity to get your hands on a very nice printer.

A while back, we acquired one of these LulzBot printers to print off some custom gaming controllers for gamers with physical disabilities (and to make some other cool stuff as well). Our boss man [Caleb] says the AO-100 is a great printer, and in my dealings and purchases with LulzBot, they seem like a great company with great support. We’re sure the hackerspaces that win these printers LulzBot is giving away will be able to put them to use quickly by making some really cool stuff.

Filed under: 3d Printer hacks, news

UPDATE: I’m working on making the visual style fit better. It really needs some work.

Yes Ladies and Gentlemen, we’re finally taking the plunge into a more robust commenting system. This one has a ton of features, but the following few have been asked for quite frequently.

• You can now edit your comments. Yes, finally. No seriously, try it. To do this, you’ll need to log in though!
• Subscription to a comment thread is now optional. Horay!
• You can now “Like” or dislike comments.

IntenseDebate is converting our old comments over, so they should begin to appear soon. Please feel free to email me directly[caleb@] with any issue you encounter using the new system. I know you’ve been asking for it for a very long time, I’ll do my best to make sure that it goes as smoothly as possible.

Filed under: news

Why toast your bread evenly when you can burn low-resolution images instead? Meet the Super Mega Mega Toaster, a University project created by [Scott van Haastrecht] for his Creative Technology course.

Now you may be thinking that this has been done before. And indeed, a bit of searching will lead you to a post about toasting Jesus.  But that is a one-shot toaster hack which simply used a stencil to block heat to create a certain pattern. This is a mechanical overhaul for the toaster concept. It uses one row of six heating elements. Each is connected to a servo motor which moves the element next to the bread or away from it based on the pattering being printed. A stepper motor then moves the bread up so that the next row can be printed. All of this is mounted in a laser-cut wood frame which makes us just a bit nervous because the purpose of the elements is to burn stuff.

See a demo of the toaster, as well as its internal components in the clip after the jump.

[Thanks Philippe]

Filed under: cnc hacks, cooking hacks

The [Prutchi] family sounds pretty cool. [David], the father, is a well educated engineer, has 70 patents, and has written two books. On his off time, he has a passion for making experimental physics accessible to the average Joe. His daughter [Shanni] is a high school student who co-authored one of those same books, and helps conduct research in the fields of Radio-Astronomy and Quantum Physics. Together, they came up with an affordable, yet very sensitive, gamma-ray scintillation probe for their customized Civil Defense V-700 radiation survey meter. Sweet.

They decided to use parts that were low cost and readily available so others could easily follow in their footsteps. A Philips XP5312/SN photomultiplier tube (PMT) and scintillation plastic are the main components.  The enclosure for the probe is a standard paint can, lined with polyurethane foam inserts to help protect the assembly and hold everything in place.

[David] says that since the probe is very portable and has a high level of sensitivity, it is an ideal candidate for radioactive mineral surveying and scouting miscellaneous gamma-ray sources. They documented the whole process and have compiled a handy PDF file for those who are interested in creating their own.
Filed under: misc hacks

If you’re serious about astronomy these days, you want to have a computer controlled telescope. Although you can easily purchase a pre-made cable that connects the two devices, where’s the fun in that? [Charles], being an avid Maker, has created a nice step by step guide so you can build your own.

This is a great weekend project, and one that even a novice electronics hobbyist should be able to tackle. It’s straight forward, rather quick, and very easy. Strip some insulation off both ends of the cable, then cut off the unneeded wires. (You’ll only be working with three of them.) Prep everything with heat shrink tubing. Crimp one end of the wires into an RJ10 plug, then solder the other end of the wires into a DB9 connector. Secure the heat shrink tubing in place, attach the housings, and you can call it finished!

[Charles] said the whole procedure only took him around 15 minutes. Total cost? Less than $17 in parts.

Filed under: computer hacks, misc hacks

[Ken Olsen] needed a bunch of analog inputs for his model railroad project. He wanted to use the Raspberry Pi board, but alas there are no analog inputs available on the GPIO header. But there is SPI. So he used an online service to design his on Analog input expansion boards.

He mentions that Eagle can be a bit of a pain to work with. For this project he decided to give circuits.io a try. This is an in-browser PCB layout tool which we looked at in a links post some time ago. The service lets you order directly from your in-browser design without the need to run gerber files or the like (boards are made using the OSH Park service). He’s very happy with the boards he got back. They feature a footprint for a connector to interface with the RPi.

The design uses MCP3008 Analog to SPI chips. Each has eight channels but [Ken] needed more than that. Since the service provides three copies of the board he made them modular by adding end connectors which chain the SPI and power rails from one board to the next. Don’t miss his full demo in the video after the break.

Filed under: news

[Lou Prado] sent in a link to his new video on using a Bluetooth headset as a garage door opener for your Android device. This isn’t a new hack, and we’ve actually seen him pull it off once before back in 2011. But we’re running this as an update for a couple of reasons. First off, we had forgotten about the hack and it’s worth revisiting. Secondly, the headset which he used with the initial hack has gone out of production. He chose a new model, and the assembly video (embedded after the break) which he made is a treasure trove of best practices to use when hacking consumer electronics.

Here’s how the hardware part of the hack goes. He removes the speaker from the headset and solders the base of a transistor in-line with a resistor to the red wire. The emitter connects to the grounded frame of the USB charging cable which is plugged into an outlet next to your garage door opener. The collector of the transistor is then connected to the garage door opener, along with a common ground connection, allowing audio from the headset to trigger the transistor to open the door.

The systems is secure based on Bluetooth pairing, which was done with his phone before starting the hardware hack.

Filed under: android hacks, home hacks

We’re still not quite sure what to call these projects, but as we’ve said before, it’s a pleasure to see what people are doing to use one remote control to rule them all. The project being developed by [Kalle Löfgren] seeks to simplify the remote controlled items in his home by combining all control into one smart phone app. The linchpin of the system is this command center which lets a smart phone send IR and RF commands to various devices (translated).

We’ve seen this done with pretty beefy microcontrollers, like this project that uses a PIC32. But the communications going on between the smartphone and the base station are very simple, as are the remote control commands which are being relayed. So we’re not surprised to find that this setup just uses an ATmega88, IR LED, Bluetooth Module, and RF module. There is no connection to a computer (the USB simply provides power via a cellphone charger). If you’re interested in how [Kalle] sniffed the protocol for each remote he wrote two other articles which you can find in the write-up linked above.

Filed under: home entertainment hacks, home hacks

We would wager that by weight this project is mostly wiring. We might go as far as betting that the wire outweighs the rest of the components 2 to 1. We’ll keep our fingers crossed that there’s never a loose connection, but for now it seems that [Kevin Horton's] NAND-based computer project is up and running. Very nearly ever part of the build is based on NAND gates, which is why the point-to-point wiring is so crazy. There is one peripheral board which uses some non-NAND components, but he eventually plans on replacing that to make the system…. pure?

Now get ready for the crazy part. This is just one half of the program counter! There’s another board that looks just like it. The two join at least a half-dozen other boards of similar size and complexity to make a functioning computer. Crazy! The post shares a ton of details, but you can also just skip down after the break to see a video of it running a program.

If you’re wondering how a NAND-based computer works you should make your way through this online course.

[Thanks Jeroen]

Filed under: computer hacks

Don’t get us wrong, we love our Raspberry Pi. But if you’re merely running a Linux image without adding a hardware hack into the mix you’re missing out on part of the power for which the platform was developed. This project is a great example of how to embrace the Raspberry Pi’s ability to deliver both low-level hardware access, and solid embedded Linux performance. [Dan Ankers] and [Threeme3] have developed a program which turns the RPi in to a WSPR transmitter. The GitHub readme shares many of the details on how it was done. But you’ll also want to dig through the .c file to see how they’re making use of the GPIO header pins.

[William Meara] sent in the tip for this. He’s been featured on Hackaday previously for his work with WSPR (Weak Signal Propagation Report). It’s an amateur radio protocol which lets you communicate over very long distances using relatively weak transmitters. The trick is to use computing power to find the signal hidden in all the noise. Be warned that you do need a HAM license to try this out, but otherwise all you need to connect to the board is a low-pass filter and an antennae.

[via SolderSmoke]

[Photo credit: WSPR hompage]

Filed under: radio hacks, Raspberry Pi

Have an awesome invention that you want to create and sell to the world? Think you have everything all planned out and you’re ready to just let the money flow in? Maybe not. Take a few moments and read [Jonathan]‘s first hand experience of a maker start up business that didn’t go anything like he had planned.

[Jonathan] thought he was ready. He had created a unique product and, by taking pre-orders, didn’t have to front any of his own capital. He had shown that there was demand for such a device. The big problem…supply. Selling things was the easy part. Actually making them was another story. Every step of the way had complications. Printing errors, parts suppliers backed out, an international money transfer didn’t go through, postage rates increased, suppliers sent the wrong parts, and he and his wife had a baby. His stress levels were through the roof knowing that his customers had prepaid and were waiting through all the delays.

In the end, [Jonathan] learned a lot and survived the journey. He is currently working on his next invention. If you’d like to learn more about his experiences, you can message him personally.  There’s also a Pianocade features video after the break.

[via Adafruit]

Filed under: lifehacks, misc hacks