Hackaday doesn’t always get the entire back story of a build. The usual assumption is that someone decided to build something, and with just a little bit of effort the project makes it into the Hackaday tip line. This doesn’t do justice to the builder, with skills honed after years of practice and experience. A 200-word summary is deceiving, and makes everything look almost too easy. [Michal] decided to buck that trend and sent in his half-decade long adventure of becoming one of the best micro-scale machinists we’ve ever seen.
In 2006, with years of robots made out of hot glue and cardboard behind him, and the quality of 3D printers not up to his exacting specifications, [Michal] snapped. He sunk the better part of $3000 into a Roland MDX-15 desktop mill. After several months of futzing about with acrylic sheet, [Michal] came across the wonderful machining properties of modeling board.
Determined to do something useful with this modeling board, [Michal] started looking into resin casting. Casting in resin is a common technique in the artist and model maker communities to mass produce small plastic parts. After getting his hands on eight liters of polyurethane resin, [Michal] made a useful part guiding the direction his skill set would grow in the coming years.
After years of experimenting with techniques, materials, and mediums, [Michal] eventually honed his craft and was able to finally start building real robots. These projects were a far cry from the cardboard and milk jug contraptions made earlier in his career. [Michal] was now producing incredibly precise gear assemblies with accuracies within 0.002 mm.
You may remember [Michal] from his robot with pivoting wheels we showcased last week. He got a lot of email from people wanting to know how to start delving into his unique blend of artistry, engineering, and craftsmanship. The good news is you can now learn from his mistakes, so a planetary gearbox shouldn’t take more than a few months to finish.
[Paul McGuinness] owns a Series III Land Rover, and as the vehicle as formerly used by the British military, it’s lacking some of the modern amenities he was accustomed to. Overlooking the lack of power steering and all-around drum brakes, the one item that [Paul] really missed was a buzzer that let him know when he left the lights running.
On more than one occasion, he’s had to have “The Sarge” jump started after leaving the lights running all day. Explaining the humiliation involved with jump-starting a Land Rover with a Nissan Micra (an unfortunate excuse for a vehicle, known here in the states as the Nissan Versa) in his blog, [Paul] decided that he’d had enough – it was time to build a headlight warning buzzer.
The circuit itself is straightforward, consisting of a normally closed relay connected to his headlights and ignition, along with a buzzer. When the key is in the ignition and the lights are on, the relay is open and the buzzer is silent. However, if the lights are on and the relay is not supplied power from the ignition, it closes and sounds the alarm.
A simple fix for a frustrating problem – we like that.
DIY book safes are well and good, but if you give someone enough time to peruse your book collection, the 3-inch thick “Case study on Animal Husbandry Techniques during the 14th Century” is likely to stand out among your collection of hand-bound “Twilight” fan fiction. In an attempt to teach his friend a bit about microcontrollers and circuits, [Jonathan] spent some time adding a bit more security to your run of the mill book safe.
The pair started out with the time-consuming process of gluing the book’s pages together and creating enough hollow space for both storage and the electronics. With that out of the way, they installed a latch and servo motor inside the cavity, the latter of which is controlled using an Atmega328p with the Arduino bootloader. To gain access to the goodies stashed away inside, Jonathan hooks up a small PS/2 keypad and enters a passcode. This triggers the servo motor, opening the latch.
While the latch likely only adds a nominal bit of security to the book safe, it’s a fun enough learning exercise to justify the time spent putting it together.
Continue reading to see a short video of [Jonathan’s] electronic latching book safe in action.
Continue reading “Adding an electronic lock to a DIY book safe”