Tiny micro desktop smoke machine

Creating your own circuit boards at home is pretty easy, if you have a laser cutter, a couple of hours, and a vat of heated ferric chloride. Luckily, I had access to all three, so had the chance of trying out a few PCB designs, to get the overall physical size as small as possible.

I bought some tiny little glass vials off the intertubes (to hold the vape juice) and 3d printed a little holder to keep everything nice and neat.

I honestly thought I’d cracked the design; everything was nice and small and super-neat, and worked really well.

The only problem was, because the vial was so small, the “smoke machine” would run out of juice after about 20 minutes of continuous use. I was in two minds about whether to just accept this as a “feature” of the device when something else happened that  required (yet another) complete redesign:

Everything that uses microelectronics requires a power and a ground wire. To be able to communicate with the device (to tell it when to turn the coil on and off, remotely, for example) we also need at least one data line (lots of electronic devices require two data lines, or a data and a clock line, but I managed to come up with a system that allowed us to use just a single wire for bi-directional communication).

These three wires need to connect to a “controller” (which we use to send data to control the device remotely). During a test, I put the plug in back-to-front, inverted the power and ground lines and “pop!” everything suddenly stopped working (the acrid smell of burnt electronic components took a while to register, as the air was thick with vapourised vegetable oil!)

Given that I’m supposed to be relatively competent with electronics, and still managed to mess things up by putting the wires the wrong way around, I decided it was time to reconsider the whole design….