A Homebrew Weller RT Soldering Station

January 6, 2020 by Tom Nardi 15 Comments

Like a number of hackers before him, [MarcelMG] was impressed with Weller’s RT soldering iron tips, but considerably less enthused about the high purchase price on the station they’re designed to go into. Inspired by similar projects, he decided to try his hand at building his own soldering station which reaps the benefits of these active tips without the sticker shock.

The station’s user interface was kept intentionally simple, with little more than a four digit LED display to show the temperature and a rotary encoder to set it. The display alternates between the current temperature and the set temperature every few seconds while the knob is being turned, and if you push it in, the set temperature will be saved as the default for next time.

[MarcelMG] also included a feature that drops the iron’s temperature when it’s sitting in the holder, reducing tip wear and energy consumption. He originally planned on using a Hall effect sensor to detect when the iron was holstered without needing to physically interface with it, but in the end he realized the easiest approach was to simply connect one of the input pins on the microcontroller to the metal holder. Since the tip is grounded, he could easily detect if it was in place with a couple lines of code.

Speaking of which, the station is powered by an ATtiny24A with firmware written in C using the Atmel Studio IDE. [MarcelMG] mentions that the limited storage on the 24A was a bit of a challenge to work around, and suggests that anyone looking to follow in his footsteps uses something with a bit more flash under the hood. The LED display is a very common TM1637 type, the rotary encoder was salvaged from a radio, and the power supply was from an old laptop. All told, this looks like a very economical build.

Depending on your needs, a DIY soldering station can either have features to rival the commercial models or be exceedingly simplistic. In either case, the advent of low-voltage irons and active tips have made self-built soldering stations much more approachable. Attempts without the use of these modern niceties tended to be somewhat less glamorous.

Origami Busts A Move With Dancing Paper

March 3, 2015 by Adam Fabio 20 Comments

Origami cranes are cool, but do you know what’s cooler? Origami cranes dancing to the beat. That’s the challenge [Basami Sentaku] took on when he created Dancing Paper (YouTube link). You might remember [Basami] from his 8 bit harmonica hack. In Dancing Paper, paper cranes seem to dance all on their own – even performing some crazy spinning moves. Of course, the “magic” is due to some carefully written code, and magnets, lots of magnets.

Using magnets to move objects from below isn’t a new concept. Many of us have seen the “ice skating pond” Christmas decoration which uses the same effect. Unlike the skating pond,Dancing Paper has moving parts (other than the cranes themselves). Under the plastic surface are a series of individually controlled electromagnets. Each of the supporting dancers has a line of four magnets, while the featured dancer in the center has a 5×5 matrix. The 41 electromagnets were wound around bolts with the help of a Tamiya motor and gearbox.

The actual dance moves are controlled by C code which appears to be running on an Atmel microcontroller. Of course a microcontroller wouldn’t be able to drive those big coils, so some beefy TO-220 case transistors were employed to switch the loads. The cranes themselves needed a bit of modification as well. Thin pieces of wire travel from the neodymium magnets on their feet up to the body of the crane. The wire provides just enough support to keep the paper from collapsing, while still being flexible enough to boogie down.

Click past the break to see Dancing Paper in action!

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