everything’s better with fireballs

I never intended for the Selleck Striker to include fireballs. But this time last year we started thinking about fireballs for something else and got all the pieces together, so they were really just waiting around for something awesome like this. Here’s how it’ll work.

The fire itself is created by igniting “flash paper”, which is a nitrocellulose paper used by magicians to create relatively safe indoor fire effects in their act. Basically the stuff flares up and it’s gone… no burning embers, hardly any ash at all. It is fire, but you can basically hold it in your hand, it’s there and gone that fast.

The flash paper is ignited by a model rocket engine ignitor, which is essentially a tiny incandescent filament with some flammable paste packed around it. You apply 6-12 volts with enough current and it flares up breifly, but plenty long enough to light the flash paper. The Arduino can’t supply nearly enough current to light it, so I’ll end up using a transistor to switch a higher-current (and slightly higher voltage) power supply to the ignitor.

For now I’m just concerned with the hardware. I’d like to have a replaceable “charge” that can be unplugged once it goes off, and replaced with a fresh one. So the sketch below shows a small metal tube with a 1/4″ phono plug on one end that plugs into a matching jack behind the Tom Selleck head.

fireball_charge

The tube is copper and the end fitting just slips on snugly, but everything else turned out just like the sketch:

For now I’m using a 9V battery touched across the plug’s contacts. The trick, it turns out, is packing the right amount of flash paper in the right way. It took  a few tries, but I think the third attempt got it right:

3 Responses to “everything’s better with fireballs”

  1. Arturo Gonzalez writes:

    hey man… im from mexico, monterrey city. i was searching for a hi striker with lightning, i remember seeing one on the net, but i donñt remember where. well, the point is tha i found out your blog and saw the tom selek hi striker you made, and i came up with a business opportunity for you if you are interested. I work for an advertising agency, and im allways looking for new stuff to offer to our clients. please, let me know if you are interested to know what´s about…

  2. Zach writes:

    Look into using a model airplane engine glowplug.

    They take a couple volts and are reusable.
    I made small flash pots with blackpowder and I was able to use one glow plug for 20+ “shots” before they gummed up.

    I think the flash paper might be a little cleaner.
    Keep up the fantastic work.

  3. joel writes:

    Thanks Zach, I’ll look into that for future fireballs!