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.
[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.
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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.
[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.
[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.
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.
Quick: which pins are used for I2C on an ATmega168 microcontroller?
If you’re a true alpha geek you probably already know the answer. For the rest of us, ChipDB is the greatest thing since the resistor color code cheat sheet. It’s an online database of component pinouts: common Atmel microcontrollers, the peripheral ICs sold by SparkFun, and most of the 4000, 7400 and LMxxx series parts.
The streamlined interface, reminiscent of Google, returns just the essential information much quicker than rummaging through PDF datasheets (which can also be downloaded there if you need them). And the output, being based on simple text and CSS, renders quite well on any device, even a dinky smartphone screen.
Site developer [Matt Sarnoff] summarizes and calls upon the hacking community to help expand the database:
“The goal of my site isn’t to be some comprehensive database like Octopart; just a quick reference for the chips most commonly used by hobbyists. However, entries still have to be copied in manually. If anyone’s interested in adding their favorite chips, they can request a free account and use the (very primitive at this point) part editor. Submissions are currently moderated, since this is an alpha-stage project.”