I have a good temperature controlled soldering iron on my work desk but sometimes you need soldering equipment in the field / car / or some other place in the house and I didn't want to unplug my rather heavy desktop iron. So I looked around and decided to use some off the shelve components to make a cheap but still reasonable quality, temperature controlled soldering iron that can be used any place (small and light) and can be powered from different sources (LIPO, car battery, power adapter or just my desktop power supply) ! I decided to use the HAKKO 907 as cheap alternatives are readily available and used an off the shelve temperature controller and DC/DC step up convertor as the 2 main components.
The off the shelve HAKKO controller from Ebay comes shrink wrapped with display and buttons integrated on the PCB. To make it more useable and have everything integrated into a nice case, I first desoldered the display such that I can put it on the front panel of the case.
The DC/DC boost converter is a 150W version which is a good safety margin. I regulated the output to 22V as the manufacturer of the HAKKO controller suggest anything between 19V and 24V ...
While at my FabLab, I used the laser cutter to make a custom box with 3mm MDF. I use the following website to quickly prototype boxes :