I want to make a candle flame light up triggered by a microcontroller. Is it possible? I only want to light it up. Not turn it down. Moreover, this is for a one-time use so the candle burning down and becoming shorter is not a problem.

  • Do you want it to get brighter and brighter in steps? – Samee87 Jan 30 '17 at 22:47
  • 3
    There are some pretty good responses on this subject at forum.arduino.cc/index.php?topic=70373. If one of those works for you please answer your own question. – per1234 Jan 31 '17 at 0:32
  • 1
    You must summon the lord of the nether world to get the most prudent solution. I will spell his name with whitespace between each letter: M a j e n k o – user400344 Jan 31 '17 at 12:30
  • 1
    Have someone hold the candle and a lighter. Then, have the Arduino light an LED. Once they see the LED, have them light the candle. Once the LED is out, have them blow out the candle. Problem solved. – cbmeeks Jan 31 '17 at 21:04
  • @Samee87 Not at all. I just want to light it up once and that is it. – Ananda Feb 2 '17 at 12:20

A simple solution is too use nichrome wire which when a current is passes through it will heat up. You could wrap some of this wire around the wick on the candle and then power it either straight from your arduino or you could include a capacitor. This is much safer than some of the other methods which use potentially dangerous high voltages.

I tested the nichrome wire approach and it works! See following video clip. 2 Ohm resistance and 19V for 1 second. https://1drv.ms/v/s!AvcBubMtAczvifYZwoESAhUodOoqRA

  • Even when nichrome is white-hot, it is dubious that it can light a wick. Did you try? It will also not autoadjust its length as the candle becomes lower. – user400344 Jan 31 '17 at 18:41
  • @user400344 i have not lit a candle with nichrome wire but im sure if i was tightly wrapped at the bottom of the wick it would light. However as you stated it will not autoadjust obviously and so this is a problem. Maybe a complicated servo system could be used. – Stratmoss Feb 1 '17 at 18:59
  • I think this is the solution that I am looking for if the wire is capable of becoming hot enough. I will try let know what happens!! – Ananda Feb 2 '17 at 12:16
  • @ANANDAPADHMANABHANS yeah make sure you buy the correct wire. Look at the sellers details. – Stratmoss Feb 3 '17 at 18:01

If you have a circuit, you can switch it on and off using a microcontroller.

So what you need is a circuit which can light a candle. Have a look at these:

DIY arc lighter

CCFL Inverter becomes an Arc Lighter?

I predict your main problem will be dealing with the fact that candles get shorter as they burn.

  • Actually in my case that is not a problem as this is for a strict one time turning on. I am sorry I was not clear about that in my original post. I will try these out and see what happens!! – Ananda Feb 2 '17 at 12:18

Use two rods at either side of the candle, and engineer two motors to slide op and down these rods. Meccano kung-fu.

Use limit switches to detect the highest and lowest positions for both motors. Mount a LED on one motor, and a laser (5 mW red is plenty). From the bottom, have both motors ascend, until the LED can receive data transmitted by the laser. Yes, you can most certainly use a laser diode for Serial.print.

When at the right height, engage gasburner. You can use an LDR (shielded against light from the sides with heatshrink) to check if the candle has been lit - shortly after disengaging gasburner. You will need a reading prior to each ignition.

Let me know how that works out.

  • 1
    This will not be a romantic candle. – user400344 Jan 31 '17 at 1:05
  • Unless you're Bender from Futurama. But he would prefer a 6502 instead of the Arduino. – cbmeeks Jan 31 '17 at 21:00

Functioning proof of concept.

Ni-chrome wire from hair dryer, approximately 2 Ohms, powered by 19 V for about 1 second. video of proof of concept. Lots to work out still, but this obviously can work.


Have you considered using a servo with a high torque, and a piezo-electric butane lighter?

The high torque would be required to push the lighter button as these tend to be rather stiff. Also, they do not always work on the first press and so a few attempts by the servo may be required. A Dynamixel AX-12A could do the job, but pricey, and could be overkill.

To save some money and time, measure the torque required to push the lighter button first and then get a servo/actuator to match.

Alternatively, use a gas oven lighter, again in conjunction with a linear actuator.


Is it possible?

Not only is it possible, I will also provide all the code you will never need to light it up reliably:

While (!candleislit())

That's all you need too light up a candle.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.