Arduino Forum

Topics => Interactive Art => Topic started by: theantidote13 on Aug 25, 2011, 03:58 am

Title: How to make candles light on command?
Post by: theantidote13 on Aug 25, 2011, 03:58 am
I was wondering if anyone has tried to approach the fire issue with an Arduino. Is there any way to light candles syncronized to music? I know you can do it with LED's, but is there any way to make the same current switch some sort of inexpensive ignition source?
Title: Re: How to make candles light on command?
Post by: theantidote13 on Aug 25, 2011, 04:01 am
Just some further details....this project only needs the candles to light once, and I'd like the igniters to be as inexpensive as possible, so i can do this on a large scale. This is for a marriage proposal....so...let me know if you can help!
Title: Re: How to make candles light on command?
Post by: keeper63 on Aug 25, 2011, 05:09 am

Just some further details....this project only needs the candles to light once, and I'd like the igniters to be as inexpensive as possible, so i can do this on a large scale. This is for a marriage proposal....so...let me know if you can help!


Well - you're going to need a source of electrically controlled heat, and that's going to take some current - so plan on a large power supply, for one thing.

You're going to need to do some experimentation; I would try a couple of things (both will need to be switched by a large transistor or mosfet - look in the tutorials for an example; you'll basically need to do the same thing as switching on a relay or solenoid - but you won't need the flyback diode, as you'll be switching a resistive load, not an inductive one):

1. Use a piece of nichrome wire from a toaster; form small coils that can be slipped over the candle wicks, switch them to heat them up.

or

2. Carefully break open some regular light bulbs, and extract the filament; these will be very, very fragile - you'll basically want to fix them against the wick, then wire them up to switch on (use 12 volt bulbs if switching with a transistor - for household mains-current bulb filaments you'll want to use an SSR or something like that).

Another option (though it may produce sparks and smoke) might be to try to use rocket motor igniters.

For all of these, you might want to try "attaching" the igniter (whether nichrome wire, bulb filament, or rocket igniter) to the wick with some dribbled wax. Another option would be to attach a small piece (< 1 cm) of fuse with wax to the wick, then ignite that (again, sparks and smoke might be an issue).

:)
Title: Re: How to make candles light on command?
Post by: AWOL on Aug 25, 2011, 12:42 pm
Quote
Carefully break open some regular light bulbs, and extract the filament;

Make sure they're switched off when you try this.

Would Estes model rocket igniters work?
Title: Re: How to make candles light on command?
Post by: keeper63 on Aug 26, 2011, 12:32 am

Quote
Carefully break open some regular light bulbs, and extract the filament;

Make sure they're switched off when you try this.


Heh - maybe I -should- have mentioned that... :)

Would Estes model rocket igniters work?


I would think if they could ignite a rocket, they could light a candle, which is why I mentioned them. However, they will throw off sparks and smoke, which could be an issue, depending on the surroundings...
Title: Re: How to make candles light on command?
Post by: keeper63 on Aug 26, 2011, 12:35 am
I just thought of another possibility - wrap a small amount (2-3 cm) of fine-gauge steel wire (a piece pulled from steel-wool would probably be good) around the candle's wick, and switch current through it - it should heat up to a fire-producing glow with a large enough current source and light the wick before it burns out...
Title: Re: How to make candles light on command?
Post by: AWOL on Aug 26, 2011, 10:02 am
(sorry, missed your ref to igniters)
You could maybe help the wick along a little by soaking the top in a strong solution of sodium or potassium nitrate, and letting it dry out.
Depends on the legaglity of these compounds in your jurisdiction.

Thinking further, some more exotic nitrates (strontium for example) could yield some interesting coloured flames.
Title: Re: How to make candles light on command?
Post by: Chagrin on Aug 30, 2011, 04:12 am
You can make a simple igniter using a single strand of copper wire from a stranded cord (like a lamp cord) and looping it over the head of a paper match. Mate your thin wire to thicker wires near the match head, of course. Steel wire would work as well -- just find something thin. I think the nichrome in a toaster would be too thick for low amperages. Might even work with a few strands of thin steel wool. Then you need a nice piece of steel pipe and a few cups of... oh wait... what were we making?

Ahh, brings back memories  ]:)
Title: Re: How to make candles light on command?
Post by: Bobnova on Sep 05, 2011, 07:25 am
If you're feeling really perverse about it you can pull the potassium nitrate out of blackpowder by soaking it in water.
Standard disclaimers about legality and safety apply.

Actually if you have nicely fireproof surroundings and pre-burnt candles, a hot wire in a small pile of blackpowder is flat out guaranteed to ignite a candle....
I don't really recommend that though.
Actually, I don't recommend anything involving blackpowder, when you get down to it.


I'd use estes rocket igniters, this is exactly what they're built for, after all.
Title: Re: How to make candles light on command?
Post by: radman on Oct 03, 2011, 10:46 pm
Rocket igniters, potassium nitrate, blackpowder ]:)
What is the music, the 1812 Overture?

There are probably questions to be asked about how exactly the ignitions are to be synchronised with the music as lighting a candle is fairly slow. I am presuming this is indoors, so having a fire extinguisher to hand will be sensible.
There is going to be a lot of wiring, and the viewing angle will be very important.
Mirrors might enhance the effect.

If you treated the wicks with something like potassium nitrate could you ignite them with an Arduino guided laser?
Not very romantic wearing goggles though!
Title: Re: How to make candles light on command?
Post by: theantidote13 on Nov 22, 2011, 12:05 pm
I love that you guys took this and ran to the logical, explosive conclusion. I am proud of you gentlemen! Hahaha

cr0sh, I love your ideas involving nichrome wire and steel wool, they sound right for this situation. I am actually lighting off paper lanterns and trying to automate the whole process....it is proving to be difficult, but will be worth it hopefully! Thanks for all your help.
Title: Re: How to make candles light on command?
Post by: Zeph on Jan 31, 2012, 08:31 am
I used the first approach mentioned by Chagrin, a  bit over 40 years ago - a single copper strand from a fine-stranded lamp cord wrapped around a match head and candle wick; on either side of the candle were two clips for holding the copper strand (this could be reloaded), wired to 120v and a concealed switch on the other side of the room.  (Hey, computers were housed in big air conditioned raised-floor rooms in those days, not thumbnail sized).  I could wave towards the candle across the room and press the hidden switch with my other hand, and pfft the candle would light.  The candle in this case was stubby and in a holder, so the clips holding the strand were not visible unless you got close and looked into it, mostly you just saw the flame.

Be safe!  The only BIG fire you want to light is in your sweetie's heart.
Title: Re: How to make candles light on command?
Post by: nakulkundra on Sep 22, 2016, 06:48 am
Why don't you use a Simple Servo with a Click Gas Lighter ?
Title: Re: How to make candles light on command?
Post by: cristinon on Oct 20, 2016, 10:44 pm
Try using rocket igniters: Link (http://www.advantagehobby.com/180782/ARO89895/89895-Frst-Fire-Jr-Initiator-FG-Composite-Mtrs-3-HAZ/?gclid=CjwKEAjw1qHABRDU9qaXs4rtiS0SJADNzJisqdGMzNf1Evj6bSlBgu5ND9zbCIavm8YX5mKiy_Pe1xoCqS7w_wcB). You can probably find them for cheaper.
Title: Re: How to make candles light on command?
Post by: jseery on Dec 04, 2016, 05:56 am
I've used vape coils which are nichrome coils.  They do require a significant amount of power. I use 14V 1800 mAh batter rated for 20C. 

https://www.amazon.com/Premium-Pre-built-Clapton-Coils-Gauge/dp/B015GLAZAW/ref=sr_1_9?ie=UTF8&qid=1480827223&sr=8-9&keywords=vape+coil
Title: Re: How to make candles light on command?
Post by: ljsweeny on Oct 28, 2017, 08:01 pm
Standard nicro wire from an old hairdryer works good, see attached video, prototype. This is about 2 ohms driven by 19 V for 1 sec using a relay. Need to play with parameters. Also note that alegator clips interfere with flame so I'll be moving those away.  Trick is to keep all this lightweight and unobtrusive.


prototype video (https://1drv.ms/v/s!AvcBubMtAczvifYZwoESAhUodOoqRA)