Smelting Metal In Your Microwave Oven

December 19, 2011 by Mike Szczys 39 Comments

Grab some scrap metal and a microwave oven and you’ll be casting your own metal parts in no time. [Mikeasaurus], who is known for doing strange things like making Silly Putty magnetic or building his own spray paint bottles, doesn’t disappoint this time around. He read about microwave smelting in Popular Science and is giving it a shot himself.

The image above shows him pouring an ingot. He build an insulated brick enclosure inside of the microwave oven, then set it to go ten minutes for a 50/50 lead/tin mixture, or fifteen minutes for silver. This will vary based on the power rating of your microwave. You can see in the video after the break that the setup gave him some trouble shortly after pouring. It wasn’t a problem with the molten metal, but spontaneous combustion of the rigid foam insulation that did him in. We shouldn’t say ‘I told you so’, but that insulation says right on it that it’s flammable!

This isn’t the first time we’ve looked at casting metal melted in a microwave. Check out this other version posted back in 2005. Continue reading “Smelting Metal In Your Microwave Oven” →

A Wooden Engine Powered By Compressed Air

December 17, 2011 by Jeremy Cook 23 Comments

You may have seen an air powered engine at some point, but most are made out of some sort of metal. This engine, however, is made entirely out of wood (and fasteners). One might wonder how a design like this was conceived, but this may be explained by [Woodgears.ca’s] tagline: “An engineer’s approach to woodworking.” It should also be noted that this is actually [Matthias’] sequel to “Wooden Air Engine 1.”

The engine itself is a neat device in that it uses power from compressed air (or suction from a vacuum cleaner) to make the piston and connecting rod cycle back and forth to spin a flywheel. The other connecting rod is used to switch which side of the “clyinder” received air pressure (or vacuum). A really neat mechanical assembly, and one that took a good amount of skill to make out of wood. Check out the video after the break to see how it all works!

[youtube http://www.youtube.com/watch?v=ngb4SYR74m4&w=470&h=315%5D

If you’d like your woodworking to be more automatic, check out this post about how to set up a CNC router for your personal use.

Advent Calendar Of Circuits

December 16, 2011 by Mike Szczys 2 Comments

We missed 60% of it already, but luckily you can easily watch the back catalog of [Alan Yates’] 2011 Advent Calendar of Circuits. As with traditional Advent Calendars he’s got a treat for every day in December leading up to Christmas. Instead of chocolate, the treat is a video about a different electronic circuit.

We didn’t find a playlist link, but you can just head over to his YouTube channel as each day is clearly labelled in the video titles. He starts off with a current limiting voltage regulator. A couple of days later he busts out a metal detector that will be fun to play with. Day 7 brings an AM transmitter/receiver pair, and Day 12 illustrates a burnt-out Christmas light detecting tool which we’ve embedded after the break.

The sheer volume of projects he’s putting out every day is remarkable and delightful. He doesn’t even limit himself to one video a day, but has posted several ‘extra’ editions with quick, circuit demos. Continue reading “Advent Calendar Of Circuits” →

Twitter-enabled Candy Machine Dispenses Treats On Command

December 15, 2011 by Mike Nathan 4 Comments

[Michael Nilsson] and [Markus Olsson] were contemplating how to motivate members of their dev team when they came up with the idea of a candy machine that automatically dispenses treats when someone has earned it.

They picked up a candy machine, a continuous rotation servo and a controller, then got busy automating the dispenser. The mechanism behind the operation is actually pretty simple as you can see in [Michael’s] writeup. They disassembled the machine, removing the gear from the manual crank, attaching it to the servo. Once the servo was mounted place, they installed the servo controller and connected it up to a spare laptop.

The heavy lifting is done by a Ruby script that uses the Twitter API to scrape any mentions of @_macke_ or @sidpiraya. Incoming messages are checked for the words “give” and “candy”, triggering the machine to fork out some sweets.

If you think that their hard work deserves a bit of recognition, feel free to send them some candy by tweeting “give @_macke_candy” or “give @Sidpiraya candy”. Just remember to be considerate – nobody likes spam, not even candy machines!

If you’re interested in seeing the machine in action, be sure to check out the candy dispenser’s live stream at giveawaycandy.com.

Rudolph Toy Hacked To Announce Incoming Email

December 14, 2011 by Mike Nathan 6 Comments

email-reading-reindeer

Tis the season for hacking, and [Nick McClanahan] at the GadgetGangster is certainly showing off his Christmas spirit with his most recent creation. He had an animatronic Rudolph the Red Nosed Reindeer toy sitting around and thought it would be fun to convert him into an email reading machine.

He tore open the toy, removing its innards, disconnecting the built-in speaker and servos from the original PCB. He then extended wires from those components outside of the body before reassembling the toy. The reindeer is controlled primarily using a Propeller Platform, with an E-Net module and a small audio amp taking care of network communications and audio output, respectively.

Most of the work is done by the software [Nick] is using, which allows Rudolph to periodically check his Gmail inbox for new messages. When the message count increases, the reindeer springs into action, moving and lighting up his nose before announcing the sender’s name.

He’s using a phonemic voice synthesizer for the output, which does the job, though we would go mad if we had to listen to it all day. Since the reindeer is connected to his LAN, it might be feasible to run the data through a more robust voice synth on a PC, returning a better-sounding audio clip for playback.

Check out the video below to see a short clip of Rudolph in action.

Continue reading “Rudolph Toy Hacked To Announce Incoming Email” →

Simple IR Sensor Simplifies Laptop Audio Control

December 13, 2011 by Mike Nathan 5 Comments

tiny-ir-tv-remote-receiver

[Owen] has a fairly big project in the works, where he’ll need to use infrared light to send data wirelessly between two nodes. The only problem with his grand plan is that he has never built anything of the sort. As a learning exercise, he decided to try his hand at building a wireless control interface for his laptop, which he uses to play music while doing homework.

His laptop usually sits across the room from [Owen], where it is connected to a speaker and amplifier. He hates getting up repeatedly to change songs, so he figured he might as well build an IR receiver to control Winamp that responds to commands from his TV’s remote control. Using his Open Bench logic sniffer and an IR receiver from an old VCR, he deciphered his remote’s encoding system. He then programmed an ATtiny13 to decode messages received by the IR sensor, sending them to his laptop via USB.

He packaged things inside a tiny mint tin, which he hangs from a desk lamp while in use. Now he can easily perform just about any action in Winamp with a few button presses on his remote. [Owen] says that he’s incredibly happy with the results, and now that he has a firm grasp of IR signaling concepts, we can’t wait to see what he builds next.

Nine Not-so-easy Steps To Build A Singing Tesla Coil

December 10, 2011 by Mike Szczys 7 Comments

We love a good Tesla coil music performance, but have never really considered building our own. After reading [TheHomebrewGuru’s] guide to musical Tesla coils we’re still not considering it. Whether or not you’re going to undertake the project, his massive writeup is worth a look.

The tutorial begins at the beginning, with a bit of background on these devices, including what they are, where they came from, and the electrical theory behind them. From there it’s on to the build. This isn’t a go-out-and-buy it type of project. You’re going to need some ingenuity to hunt down parts that will work, and will work with each other.

The image above shows a partially built device, using sheet metal ductwork covered in foil tape as the torroid at the top. The column is wrapped in wire, forming the secondary coil, and the wooden base is ready for the installation of the primary coil. Electronics will be housed between the two wood discs of the base, with a TI Launchpad board driving the music part of the hack.

There isn’t a good demo video of this playing music. But you can get the idea if you look back at the head-mounted tesla coil which did a great job of pumping out the tunes.