Introduction: Arduino Controlled Electric Candle

About: Space Technology and Planetary Exploration Engineering, working in development for Magna Parva Ltd. Also a proactive member of St John Ambulance and volunteer for various open source electronics and programmin…

When I first started playing with InstaMorth I quickly noticed that it does it pretty good job at diffusing light, so I thought I would make up an imitation electronic candle which I could reprogram. InstaMorph is a moldable plastic, which when heated up to 60C (less than 66C) it becomes soft and can be shaped/formed.

Step 1: Melting the InstaMorph

I located our Cafetiere (the glass from that will definitely be heat proof) removed the plunger and half filled it with water. InstaMorph comes out as white pellets which can be poured directly into the water. Once the pellets go from white to transparent they are ready, so take them out at they are ready to be molded.

Step 2: Drying the InstaMorph

The water is still very hot, so don't take it out with your hands and use something like a spoon. It all sticks together nicely, so you should be able to get it out in one lump.

Now before you start molding, I found it worked best if you dry out the InstaMorph as much as possible first. After about 20 seconds it can be held in your hand (about at hot as a drinkable mug of Tea) and whilst holding it I flung my arm around to try and force the water out. If you don't do this, you can get little bubbles of water trapped in the plastic, deforming the mold and stopping it from being able to stick to itself in certain places.

Step 3: The Lighting Effect

For the lighting I bought a few NeoPixel rings, where each of the LED's is individually addressable and colour changeable. I dug out a cheap Arduino Nano which I got from ebay for about £4 and connected it all together.

To wire it up, connect the 5V and GND from the NeoPixel ring to the 5V and GND of the Arduino. Connect the DIN from the NeoPixel ring to D6 of the Arduino. Finally, connect the VIN and GND from the Arduino to a 9V battery.

Then download the Arduino IDE and program the following code onto the Arduino Nano using the built in USB connector. The code relies on the Adafruit NeoPixel library, so make sure you download that too.

#include <Adafruit_NeoPixel.h>
#define DELAY_MULTIPLER 100
#define PIN 6

Adafruit_NeoPixel strip = Adafruit_NeoPixel(16, PIN, NEO_GRB + NEO_KHZ800);

void setup() {
  strip.begin();
  strip.show();
}

void loop()
{
  fire(1,random(50,500));  
}

void fire(uint8_t wait, uint8_t times)
{
  for(uint16_t t=0; t < times; t++)
  {
    uint32_t cBaseYellow = strip.Color(255, 100, 10);
    uint32_t redFilcker = strip.Color(255, 40, 0);
    uint32_t blueFilcker = strip.Color(255, 100, 100);
    
    for(uint16_t i=0; i<strip.numPixels(); i++)
    {
      strip.setPixelColor(i, cBaseYellow);
    }

    uint8_t blue;
    for(uint16_t i=0; i<1; i++)
    {
      blue = random(1,strip.numPixels());
      strip.setPixelColor(blue, blueFilcker);
    }

    uint8_t red;
    for(uint16_t i=0; i<4; i++)
    {
      red = random(1,strip.numPixels());
      strip.setPixelColor(red, redFilcker);
    }
    
    strip.show();
    delay(wait*DELAY_MULTIPLER);
  }
}

Step 4: Molding the Candle

First I molded a cylinder, which is a bit lob sided because I just did it by hand. The lid was done by flattening out some on the table then pushing the cylinder onto the flattened bit. While they are still warm the bits just stick to each other nicely.

Once set, I used a sharp knife to smooth out the edges, as there was some rough bits when I stuck the lid down.

Step 5: Base for the Candle

To stop me staring at the LED's I made a cover to go over around the base. As InstaMorph is reusable, so I simply warmed the water back up, put all the off cuts and left over bits into the water, and made another flat sheet. I molded the flat sheet around the base and LED's. The wire was a bit of a problem, so I just cut a slit, pushed the wire through, and then stuck it back together.

Step 6: Playing Around With a Spare Controller

I had a spare controller and NeoPixel ring, so I made up another one and pushed it straight into the InstaMorph. It made quite a nice lighting effect, diffusing the light and holding it into the box snugly.