There are several reasons you should have an isolation transformer. They can prevent ground loops and also prevent a device under test from having a DC path to ground (or isolate an oscilloscope from DC ground, which can be dangerous in its own right, but that’s another discussion). [Tanner_tech] noticed that finding ballast transformers for sodium vapor street lights is getting easier as more street lights move to LED technology. What to do with these transformers? Build an isolation transformer, of course.
Of course, your dumpster transformer might be a little different than the one shown in the post (and the video, below). [Tanner] shows how to work out the leads you need. A little wood work and a PC power supply case finished the project.
Judging from the comments, some people take [Tanner’s] talk about safety as an implication that a transformer makes working on mains safe. It doesn’t. It makes it safer if you know what you are doing. Working with high voltage isn’t a place to learn by doing.
If you want some practical advice, [Jenny List] has a good read for you. You probably also ought to invest an hour in watching this video that has a lot of practical advice.
Continue reading “Upcycle An Isolation Transformer”
[Peter] obviously enjoys getting to work in his wood shop. He also likes turning things into other things. With his latest project, he combines his two hobbies by turning plastic milk jugs into a plastic joiner’s mallet.
[Peter] started out by collecting and “processing” the milk jugs. Milk jugs are commonly made with HDPE. HDPE is a petroleum-based plastic with a high strength-to-density ratio. It’s easy to recycle, which makes it perfect for this type of project. We’ve even seen this stuff recycled into 3D printer filament in the past. The “processing” routine actually just consists of cutting apart the jugs with a razor blade. [Peter] mentions in the past that he’s used a blender to do this with much success, but he’s unfortunately been banned from using the blender.
Next, all of the plastic pieces are piled up on a metal try to placed into a small toaster oven. They are melted into one relatively flat, solid chunk. This process is performed three times. The final step was to pile all three chunks on top of each other and melt them into one massive chunk of plastic.
While waiting for the plastic to melt together, [Peter] got to work on the handle. He put his woodworking skills to good use by carving out a nice wooden handle from a piece of cherry wood. The handle was carefully shaped and sanded with a variety of tools. It is finished with some linseed oil for a nice professional look.
When the plastic was mostly melted together, [Peter] had to get to work quickly while the plastic was still soft. He pried the plastic off of the metal tray and stuffed it into a rectangular mold he made from some fiber board. He used a heat gun to soften the plastic as needed while he crammed it all into the mold. With the mold suitably stuffed, he closed it up and clamped it all shut.
Once the plastic cooled, [Peter] had to cut it into the correct shape and size. He took the solid chunk of plastic to his band saw to cut all the appropriate angles. He then used both a drill press and a chisel to cut the rectangular mounting hole for the handle. The plastic piece was then shaped into its final form using a belt sander. All that [Peter] had left to do was slide it up and only the handle. The shape of the handle and mounting hole prevent the plastic piece from flying off of the top of the handle. Check out the video below to see the whole process. Continue reading “Turning Plastic Milk Jugs into a Useful Tool”
[BenN] was at his local hackerspace one day when a friend stopped by and offered him a used 5AH lead acid battery. As any good tinkerer would, he jumped on the opportunity and immediately started looking around for a project to use the battery in. One of [BenN’s] recent other projects involved 12volt landscaping lights, the same voltage as the battery he was just given. At this point it was clear that he had a good start to making a lantern. This lantern project also supports [BenN’s]
obsession with hobby of preparing for the zombie apocalypse.
A lantern needs an enclosure. Over on the hackerspace’s spare-parts rack was an old ATX power supply. All of the internal electrical components were removed to make room for the battery which fit inside nicely. The landscaping light just happened to be slightly larger than the power supply’s fan cut outs. Once the grill was removed from the metal power supply enclosure, the lamp fit in nicely and was secured using silicone glue which can tolerate any temperature the bulb can produce.
The feature that separates a lantern from a flashlight is the top-mounted carrying handle and this lantern will receive one made from the wiring removed from the ATX power supply. The electrical wiring is fairly straight forward. The battery is connected to the landscaping light by way of the original ATX on/off switch. The two terminals of the battery were also wired to the power supply’s AC input connector. This allows [BenN] to connect a DC battery charger to two of the three pins in order to charge the battery. Although this is a creative way to re-use the AC connector, it leaves quite a bit of potential to accidently plug in a 120v AC cord!
[Aaron] has been wanting to build his own binary desk clock for a while now. This was his first clock project, so he decided to keep it simple and have it simply display the time. No alarms, bells, or whistles.
The electronics are relatively simple. [Aaron] decided to use on of the ATMega328 chips he had lying around that already had the Arduino boot loader burned into them. He first built his own Arduino board on a breadboard and then re-built it on a piece of protoboard as a more permanent solution. The Arduino gets the time from a real-time clock (RTC) module and then displays it using an array of blue and green LED’s. The whole thing is powered using a spare 9V wall wort power supply.
[Aaron] chose to use the DS1307 RTC module to keep time. This will ensure that the time is kept accurately over along period of time. The RTC module has its own built-in battery, which means that if [Aaron’s] clock should ever lose power the clock will still remember the time. The RTC battery can theoretically last for up to ten years.
[Aaron] got creative for his clock enclosure, upcycling an old hard drive. All of the hard drive guts were removed and replaced with his own electronics. The front cover had 13 holes drilled out for the LED’s. There are six green LED’s to display the hour, and seven blue LED’s for the minute. The LED’s were wired up as common cathode. Since the hard drive cover is conductive, [Aaron] covered both sides of his circuit board with electrical tape and hot glue to prevent any short circuits. The end result is an elegant binary clock that any geek would be proud of.
[Agy] a fabric hacker in Singapore has made a chic light sensitive LED necklace, and written up the tutorial on her blog Green Issues by Agy. The lovely thing about this hack is that it doesn’t look like a breadboard round her neck, and most of the non-electronic components have been upcycled. [Agy] even used Swarovski crystals as LED diffusers for extra bling.
Using a LilyPad Arduino with a light sensor and a few LEDs, [Agy’s] circuit is not complicated. She seems to be just branching out in to wearable tech, so it is nice that she learnt to program different modes for bright and low light (see video below). Her background in sewing, refashioning and upcycling does show through in her crafty use of an old pair of jeans and lace scraps for this project.
We love tech focused jewelry like [TigerUp’s] LED matrix pendants or [Armilar’s] Nixie-ify Me Necklace, but they do scream Geek. DIY electronically enhanced accessories are becoming more commonplace with the variety of micro-controller platforms expanding rapidly. Low energy wearable boards like MetaWear are making it easy for the tech to be discreet and easily connected to your smartphone. 3D printing is enabling us to create durable enclosures, settings and diffusers like the ones used for LED Stegosaurus Spikes. With all these things, hobby wearable projects can not only be functional and durable, but can also look great too.
Do you think this necklace would look out of place in a non-geeky gathering? Have you got any helpful tips for [Agy’s] code? Have you tried using gems or crystals as diffusers and what were the results? Let us know in the comments below.
Continue reading “Blinky LED Necklace That Actually Looks Chic”
Lucas came up with a real winner when upcycling cardboard to use as a bookshelf. It’s visually pleasing, can be built basically for the cost of glue and a mounting brackets, and you don’t have to feel bad if you decide to get rid of it later on.
What he saved in raw material cost he spent in labor. There are 23 different layers of cardboard that went into the project, not including the spacer squares between each piece. The vast majority of the time spent in the clip after the break shows a fast-time video of him cutting out the layers. It apparently took about eight hours of cutting, and we’d image he’s got a claw of a hand after all of that work.
This is hanging from a single L bracket positioned in the square opening with two nails to keep it level. We’d suggest including a better mounting technique in your design. If you have some ideas about this please let us know in the comments.
Continue reading “Make a cardboard bookshelf in less than a day”
Welcome to the first Buy Break Build at hackaday, sponsored by Adafruit Industries and Make. This challenge will be focusing on dancing Santas, or what is inside them. We’ve seen them everywhere, and may even have one or two in an attic somewhere. These annoying little guys should have enough bits and pieces inside to build some pretty interesting stuff. This time, we want to see a multi-legged walking device. We don’t care if it has 2 legs, 7 legs, or 32 legs, as long as it “walks” using its legs.
Join us after the break for the rules, the prize breakdown, and to find out who the guest judge will be!
Continue reading “BBB #1: The Santa-pede challenge”