Hackaday links: November 28, 2010

The Clock Clock

This digital display is made from several analog clocks with thick hands. Together they make something of a 7-segment display, which can be used to display the time. It reminds us of the “Shared Time” installation we covered previously. [Thanks Drum365 via Anonimiss Files]

Quickly desolder lots of parts

[Rhys Goodwin] is grabbing parts from junk PCBs but he’s not using a rework station. Instead it’s a hot-air gun and a brisk tap on the bench to send the parts flying. Well, at least he’s not using a blow-torch like [Ben Heck] does.

Binary Hero

This bank of 8 toggle switches is the controller for Binary Hero, a geeky take on Guitar Hero. When you see a decimal number come down the screen set your toggle to the binary equivalent in time or the game will be over before you know it. [Thanks Fabien]

Quick fan POV

[GMG] took a small persistence of vision board and slapped onto an oscillating fan blade. Along with a couple of magnets on the safety cage this display is a persistence of vision hack you can pull off in an hour or two.

Speed up laser etching

[James] figured out a way to cut down on the time it takes to etch multiple copies of one item with a laser cutter. It doesn’t run the laser faster, but orients the pieces in a way that means less movement of the head while the laser is not on. Read through his article and see if this method can help you out when doing some CNC work.

Carbon fiber part fabrication guide

If you’re thinking of working with carbon fiber this guide should be a big help. The example is aimed at the automotive crowd but the principles transfer quite easily. Carbon fiber parts are constructed in a similar manner as fiberglass parts. A mold is covered in a release agent, the fibers are put in place and covered in epoxy. With fiberglass the fibers are often sprayed on but carbon fiber components use woven mats of the material to build up multiple layers. Vacuum bags are used to hold the layers together, removing air and impregnating the fibers with the epoxy. This guide even outlines the construction of a vacuum pump needed for that step.

The benefits of carbon fiber are many, including strength and weight reduction. This makes it a great material for adding parts to weight-sensitive hacks such as quadcopters. But the mesh also has an interesting look which is why it shows up in custom electronics cases. The one real drawback is that when this material fails it is a catastrophic failure, tending to crumble across the entire structure rather than limiting damage to a small area. That means that a rough landing might be the end of your new parts.

[Thanks MS3FGX]

CNC machine from PC parts

[Mike Rankin] built a small CNC machine using some PC parts. He repurposed two optical drives and a floppy drive to create the plotter seen drawing the Hackaday logo above. The X and Y axes use the stepper motor controlled read heads from two optical drives. The Z axis is built using the read head hardware from a floppy drive. A 3-axis controller module from eBay drives the little machine, keeping the cost quite low at around $45.

As you can see in the video after the break it does a great job as a plotter. [Mike] doesn’t think there’s enough power in the hardware to be used as a mill. We’d still like to try adding a flexible shaft rotary tool and see if this could mill some rudimentary PCBs, but maybe you need to shell out just a little bit more for that functionality. It might also be possible to use an etchant resist marker instead of toner transfer or photo-resist.

Continue reading “CNC machine from PC parts”

Tokyo Hackerspace – Akihabara Station Video Tour

This is the kind of footage that makes our mouths water here at Hackaday. [Akiba] of Freaklabs has been kind enough to take us all on a video tour of Akihabara Station, a treasure trove for electronics hackers located in the Chiyoda ward of Tokyo. The highlight includes surplus stores, specialty electronics shops, and enough silicon to bring an engineer to tears. Rather than waste time reading about it, follow the link and check out the videos in stunning 720p.

Hackers in other parts of the world, what kind of stores and marketplaces do you have like this? Send us your pictures and videos of local marketplaces that cater to your hacking needs so we can show them off.

Gutting an air freshener for the parts

[Doug Paradis] took a good look inside the Air Wick Freshmatic Compact i-Motion and then stole all the parts for other projects. We’ve looked at adding a manual spray button or making air fresheners Internet enabled before. Those models didn’t have parts that were all that interesting, but this one has a passive infrared motion sensor. You’ll also gain three switches, a PNP transistor, and an LED.

Price seems to be all over the map for this model, but [Doug] says you can find it for $8 or less. After showing how to make a tool to bypass the triangular security screws, he explains how to access the PIR sensor. But if you want to be all you can be with the hardware, he details the modifications needed to patch into the analog and digital circuitry on the rest of the board too.

Version control for Eagle

[Jeff] set up version control for Eagle libraries and projects. He mentions that Eagle has become the standard for open source hardware projects and he’s absolutely right. We use it for our projects, and we’ve grown to expect that the posts we feature have Eagle files available in most cases.

But Eagle falls short in its library management. There is some amazing work from SparkFun to support a usable parts library, but who hasn’t added parts themselves? [Jeff] setup libraries using github so that changes and additions to the libraries can benefit all and cut the amount of time spent making custom footprints for new components and packages.

Need to source Nixie tubes?

Nixie tubes make for fun projects but the fun can’t start until you get your hands on the hardware. Well, [Dieter’s] got you covered with his one-stop repository on Nixie tubes and where to get them. We know that Woz’s watch isn’t currently available because of a lack of tiny tubes an obsolete accelerometer. Ladyada’s Ice Tube Clock depends on a rare 8-digit VFD tube. But you can get around parts obsolescence by adapting these designs for an available replacement. So when you take on the Dekatron Timer or a Bottled Nixie Clock you’ll know where to turn for the goods.

Update: Our mistake about Woz’s watch.  It wasn’t a tube shortage that put it out of production.

[Thanks Aaron]