Hackaday Links: December 14, 2014

 

The Progressive Snapshot is a small device that plugs into the ODB-II port on your car, figures out how terrible of a driver you are, and sends that data to Progressive servers so a discount (or increase) can be applied to your car insurance policy. [Jared] wondered what was inside this little device, so he did a teardown. There’s an Atmel ARM in there along with a SIM card. Anyone else want to have a go at reverse engineering this thing from a few pictures?

[Alex]’s dad received a special gift for his company’s 50th anniversary – a Zippo Ziplight. Basically, its a flashlight stuffed into the metal Zippo lighter we all know and love. The problem is, it’s battery-powered, and Zippo doesn’t make them any more. It also uses AAAA batteries. Yes, four As. No problem, because you can take apart a 9V and get six of them.

‘Tis the season to decorate things, I guess, and here’s a Hackaday snowflake. That’s from [Benjamin Gray], someone who really knows his way around a laser cutter.

HHaviing trouble wiith a debounce ciircut? HHer’s a calculator for just thhat problem. Put iin the logiic hhiigh voltage level, the bounce tiime, and the fiinal voltage, and you get the capaciitor value and resiistor value.

A harmonograph is a device that puts a pen on a pendulum, drawing out complex curves that even a spirograph would find impressive. [Matt] wanted to make some harmonographs, but a CNC and a printing press got in the way. He’s actually making some interesting prints that would be difficult if not impossible to make with a traditional harmonograph – [Matt] can control the depth and width of the cut, making for some interesting patterns.

The Mooltipass, the Developed On Hackaday offline password keeper, has had an interesting crowdfunding campaign and now it’s completely funded. The person who tipped it over was [Shad Van Den Hul]. Go him. There’s still two days left in the campaign, so now’s the time if you want one.

Cutting Glass With CNC

Breaking a pane of glass in half is easy – just score it, break it, and after practicing a few times, you’ll eventually get it right. What about cuts that are impossible with a normal glass cutter, like radiused corners and holes? For that, you’ll need CNC. Yes, you can cut glass on a CNC machine. All you need is a diamond burr or glass drilling bit, high speeds, low feeds, and lots and lots of coolant.

Cutting glass on a CNC machine doesn’t require any spectacularly specialist equipment. [Peter] is using an $800 Chinese mini CNC engraver for this project, but that’s not the only tool that was required. A fixture for holding a glass plate was also needed, but [Peter] quickly fabricated one out of acrylic.

Cutting glass with a CNC is something we’ve seen before. [Ben Krasnow] has been using diamond burrs, high speeds, low feeds, and lots of coolant to cut mirrors so expensive you don’t even want to guess.

While [Peter] isn’t getting the perfect finish [Ben] got a few years ago, he’s still milling holes and slots in glass. He’s wondering if it could be possible to mill an aspheric lens using this technique and a special spherical burr, something that would be very interesting to see, and could be a pretty good way to rough out telescope blanks.

The Halfbug

[Alex] posted up build details of his robot, Halfbot, on Tinkerlog. We’ve been big fans of his work ever since his Synchronizing Fireflies Instructable way back in the day. [Alex’s] work usually combines an unconventional idea with minimalistic design and precise execution, and Halfbot is no exception.

You’ll have to watch the video (embedded below the break) to fully appreciate the way it moves. The two big front legs alternate with the small front pads to make an always-stable tripod with the caster wheel at the back. It lifts itself up, moves a bit forward, and then rests itself down on the pads again while the legs get in position for the next step. It’s not going to win any speed tournaments, but it’s a great-looking gait.

The head unit also has two degrees of freedom, allowing it to scan around with its ultrasonic rangefinder unit, and adding a bit more personality to the whole affair.

[Alex] mentions that he’d recently gotten a lathe and then a CNC mill. So it’s no surprise that he made all the parts from scratch just to give the machines a workout. We think he did a great job with the overall aesthetics, and in particular the battery pack.

We’re excited to see how [Alex] adds new behaviors as he develops the firmware. No pressure!

Continue reading “The Halfbug”

Hand-Machined Companion Cube Can Be Destroyed and Rebuilt

[Michael Gainer] is a big fan of Portal, and it shows in the Weighted Companion Cube he made. [Michael] hand-machined the many pieces that comprise the Cube’s body and medallions out of 6061 aluminum. Dykem was used to transfer the marks for accurate machining, and the color is powder-coated to a heat tolerance of 400F. A CNC was used to make the distinctive hearts. [Michael] notes the irony was “very Portal” in having them cut by a heartless machine when everything else was done manually. The attention to detail is striking, the level of design more so when [Michael] proceeds to incinerate the poor Companion Cube with a brush burner. In the video shown at the link above, the Cube falls apart as the glue holding it together melts. When all is said and done, just grab more glue to bring that Cube back to its six-sided glory. Repeat to your heart’s content. Huge success! We have to be honest, after seeing all those pieces, we aren’t sure we’d want to do this very often. Companion Cubes have been featured in various iterations on Hackaday before, but they were never built with the idea of repeatedly destroying and rebuilding them. This novel take would make GlaDOS proud.

[Michael] has plans to put an Android device inside it with some light and temperature sensors. He wants to give it a voice resembling Portal’s turrets so it can whine when it needs to be charged or scream when it’s too hot or cold. He dubs this next project the “Overly Attached Weighted Companion Cube.” It wouldn’t be a good idea to incinerate this upcoming version, though we’d probably be inclined to if it demanded so much of our attention!

 

The Tumblemill: Homemade CNC Milling

[Jens] aka [Tumblebeer] has compiled an impressive overview of the Tumblemill, his homemade CNC mill. It warms our hearts to learn that [Tumblebeer] was inspired to pursue electronics by projects featured here on Hackaday, even if it means he dropped out of med school to pursue electrical engineering. We’re glad he’s following his passion, though, and reading through his blog reveals just how far he’s come: from fiery disaster in his first projects to a gradual obsession with making a CNC device, [Tumblebeer] has made plenty of mistakes along the way, but that’s how it should be.

His first iteration was a CNC router that used rubber wheels as linear bearings. It worked…barely. His latest build grew out of meticulous Solidworks modelling, with a moving gantry design constructed largely from aluminum, and upgraded linear motion: this time a bit overkill, using HIWIN HGH20CA blocks. Rather than sourcing a traditional spindle mount, [Tumblebeer] opted for the housing from a LM50UU bearing, which provided both the perfect fit and a sturdier housing for his 2.2kw spindle.

Visit his project blog for the details behind the mill’s construction, including a lengthy installment of upgrades, and hang around for a demo video below, along with the obligatory (and always appreciated) inclusion of the Jolly Wrencher via defacing an Arduino.

Continue reading “The Tumblemill: Homemade CNC Milling”

DIY Plotter Strives For Cheapest CNC Machine Title

Arguably, taking the plunge into the CNC hobby does indeed have potential to end up costing more than expected. But that should be no reason to deter anyone from doing it! [msassa11] shows us how to do it in full effect with his definitely unique and extremely inexpensive homemade plotter.

The design goal was to keep this machine as low-cost as possible while at the same time using materials that can be found around any tinkerer’s shop or at least purchased locally. First of all, you’ll notice that there is only one linear rail, yes, one rail for two axes of movement. The single rail was removed from an inkjet printer along with the mating bushing that originally allowed the print head to move freely back and forth. A threaded rod lead screw does double duty here, keeping the X axis carriage from rotating around the linear rail and also transmitting the force to move the carriage back and forth. Both the lead nut and bushings are held in place with cast-epoxy mounts.

uniquecnc-closeupAs unique as the X axis is, the Y sure gives it a run for its money. No linear rails are used, two lead screws are the only things that maintain the gantry’s position. To prevent gravity from pulling the gantry down and bending the Y axis lead screws, there are a couple of bearings on either side that ride along the bed of the machine. The frame material also hits the cheap target, it’s made from blank PCB board. A PIC16F877 microcontroller and a handful of mosfets control the motors. [msassa11] built this control circuit but admits it’s performance is not that great, it’s noisy and loses torque at high speed.

[msassa11] certainly proves that he is extremely resourceful with the outcome of this project. He met his goal of building an extremely inexpensive CNC machine. Check out his project page to see a ton of photos and find out what other unconventional ideas he used to build his machine.

Turning the Raspberry into a CAD Workstation

Inventables has been working hard on a successor to the extremely popular Shapeoko CNC milling machine, and to bring digital fabrication to the masses, they’ve created Easel, possibly the easiest 3D design software you’ll ever use. [Sacha] was trying out the beta version of Easel and mentioned to the dev mailing list he was running his installation on a Raspberry Pi. One of the developers chimed in, and after a bit of back and forth we now have a workflow to use Easel with the Raspberry Pi.

Easel is a web app, but since the graphics, design, and g-code generation are handled locally, even the most rudimentary CAD suite would choke the decidedly low power Raspi. Instead, [Sacha] is using the Raspberry to grab 2D and 3D files, turn that into g-code for a machine, and send it off to a Shapeoko router.

Easel doesn’t yet have local sender support that works on Linux, so a separate piece of software is used to shoot the g-code over a serial port to the machine. That’s something that will probably be added in a later version of Easel, making a Raspberry Pi a great way to control router or milling machine.