How do you make an electric spark?

Question

for use in a spud launcher. prefferably using household materials like batteries, wire, switch, lightbulb etc...

Answer 1

If you look for spud launcher videos on youtube you often see them using barbecue lighters. Not for the flame, but because those type of lighters usually have a piezoelectric mechanism to ignite the lighter fluid that works just as well to ignite the spud launcher.

Answer 2

Other answer is correct, a piezoelectric igniter is best and easiest. Just drain all of the fluid from it, and you will have only the spark.

I takes many thousands of volts to generate a spark over a fraction  of an inch, and you won't get that with a battery and a few wires. You can get it with an ignition coil from an auto, and some work.

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