Friday, July 19, 2013

The Flickering Fires Of Hell

In an effort to imbue my layout with a little more life I've added a couple of new things to the dark satanic mill; the flickering fires of hell and associated smoke. Neither fire or smoke is easy to capture with a photo so I've made a short video that should show the mill come to life.

If you've watched the video I'm sure that some of you might be interested in how I've produced the effects. I'll start with the smoke as that is easier to explain.

To produce the smoke I've fitted a Seuthe smoke generator inside the chimney (it's about 1cm from the top). You can see the smoke generator in the photo to the left; this was taken while I was testing how it works. It is actually very easy to use, you simply add a small amount of smoke fluid to the chimney using the supplied syringe and then apply electricity; it requires quite a bit of juice and I'm powering it with a 19V DC supply using the adapter from the cheap OO gauge train set I bought last year.

The flickering fire effect is a little more complex. Now I'm sure that I could probably have bought something for this purpose but I decided I'd prefer to build my own solution. Essentially the flickering is produced using five bright (6 million candles each) LEDs, 1 red and 4 yellow. These LEDs are connected to a small micro-processor (this is essentially a shrunk down Arduino) that runs a very simple piece of code to flicker the lights: randomly choose one of the LEDs, randomly set its brightness and then wait randomly up to 50ms before starting again. It's simple but effective, although I think it could improved by tweaking the minimum brightness of the LEDs.

Two simple additions which, I hope you agree, really help bring the factory to life.


  1. Astonishing. My immediate reaction was incense and I imagined your model melting and then I wondered if it was one of these new electronic cigarettes but I think they require puff. By the time you've finished all this when you are 90 it should be quite an attraction. One I will not be around to view!

    1. I must admit that when I first tested the smoke I thought it looked a bit like cigarette smoke. While it doesn't get as hot as incense would the chimney does get warm so I will be keeping a close eye on it. Also the voltage regulator to reduce the 19V down to 5V for the flickering lights gets quite hot as well. I've specifically orientated the board inside the factory to keep it away from the walls.

  2. PS You have added an expletive to my vocabulary: the flickering fires of hell.

  3. Replies
    1. Thanks Adrian. It took quite a bit of planning so it was nice that it all came together quite well. I even managed to solder everything together without burning a single finger!