Over the last year or so, cordless portable soldering irons have become all the rage. In fact, at this point a good number of Hackaday readers out there have likely traded in their full-size AC irons for a DC iron that’s only slightly larger than a pen. But before the big boom in portable irons, in the ye olden days of 2014, we brought you word of the open source Solderdoodle created by [Isaac Porras]. Based upon the Weller BP645 and featuring a 3D printed case, the DIY iron was designed to be charged from a standard USB port.
Now, [Isaac] is back with an updated version he calls the Solderdoodle Plus. It’s still based on the heating element from the Weller BP645, but now boasts twice the power, an improved 3D printed case, an intuitive touch-based user interface, and even some LED blinkenlights for good measure. As with the original Solderdoodle the hardware and software for the device are open source and you’re invited to build your own, though kits are also available through an already fully-funded Kickstarter campaign.
[Isaac] says that the temperature control functions on traditional corded soldering irons waste energy due to the large thermal mass they have to bring up to temperature. But with less thermal mass and a system of variable duty cycle pulsed power, he says the Solderdoodle Plus can do the same work as an old-school 60 watt iron while only consuming 10 watts. This allows the iron to maintain a constant 500°C for over an hour on the dual internal Panasonic NCR18500A lithium-ion batteries, and means you can charge it up with nothing more exotic than a micro USB cable.
With the addition of new tips and its adjustable power level, the Solderdoodle Plus can also be used for other tasks where precise directed heat can be useful. In the video after the break, [Isaac] shows off a “scooper tip” and a low power setting on the iron which is specifically intended for cleaning up strings and imperfections on 3D printed parts without melting the part itself. If you dabble in the dead trees, there’s also a sharp tip which can be used for your pyrography projects.
Internally the Solderdoodle Plus features a custom charge controller based on the Maxim MAX8903G, and the control board is powered by an ATtiny84A microcontroller. It also makes use of the Interlink FSLP 34-00003, a turn-key touch sensor module, and some very slick Bivar VLP-350-F light pipes for the clever LED “bar graph” interface. Overall this isn’t something you’ll be building from what’s kicking around the parts bin, but all the information is available for you to spin up your own Solderdoodle Plus if you don’t mind sourcing all the parts and getting the boards made.
Since we brought you word of the original Solderdoodle, a lot of progress has been made in the world of portable irons. The TS100 has become a favorite of hackers the world over, which has naturally inspired some very impressive DIY clones, and you can even get USB powered irons for as little as $5 USD. The Solderdoodle Plus has some serious competition this time around, but we’re always happy to root for the open source underdog. Judging by the fact the Kickstarter was fully funded in less than 24 hours, it seems we aren’t alone.