Spark gap in a metal chamber.

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Spudgun on Crack
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Thu Apr 10, 2008 8:33 pm

I am building a small but very cool and reliable potato pistol.

I modded a paintball gun grip and mounted a sparker behind the trigger, it works great and it clicks every time you pull the trigger!

I plan on having a metal chamber about 4 - 6in long by 1 in wide with a screw off cap on one end and a 1in to 1/4in reducer on the other. From there i will have a breakdown barrel kit that can go from 4in long to 18in long.

How would i go about building the spark gap in a metal chamber.

I know it can be done but i just want to see what you guys did for ideas.

Thanks.
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jrrdw
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Thu Apr 10, 2008 8:44 pm

Use insulating washers. Build the points into a small piece of PVC pipe, that would insulate.
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VH_man
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Thu Apr 10, 2008 9:13 pm

You can always hook up a Spark Plug....... and just use the entire chamber as ground.
Spudgun on Crack
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Thu Apr 10, 2008 9:28 pm

A spark plug is pretty big, I have an idea where i can get some very heavily insulated wire.

From my flyback transformer i can cut a few inches of the thick double insulated wire that comes out the top off. Its really hard to strip as i actually have a solid plastic coating on the inside.
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jrrdw
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Fri Apr 11, 2008 5:54 am

Spudgun on Crack wrote:A spark plug is pretty big, I have an idea where i can get some very heavily insulated wire.

From my flyback transformer i can cut a few inches of the thick double insulated wire that comes out the top off. Its really hard to strip as i actually have a solid plastic coating on the inside.
The metal pipe you have has a plastic coating on the inside? Did I read that right?
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psycix
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Fri Apr 11, 2008 6:24 am

Attach a adapter to connect a hose.
Get a wire trough, fill the rest with epoxy.
Bend the wire so, that it forms a nice spark gap with the metal chamber or hose adapter fitting.
Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

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Hotwired
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Fri Apr 11, 2008 6:33 am

jrrdw wrote:
Spudgun on Crack wrote:A spark plug is pretty big, I have an idea where i can get some very heavily insulated wire.

From my flyback transformer i can cut a few inches of the thick double insulated wire that comes out the top off. Its really hard to strip as i actually have a solid plastic coating on the inside.
The metal pipe you have has a plastic coating on the inside? Did I read that right?
It looks more like the wire coming off his flyback transformer has a solid plastic coating.
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rcman50166
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Fri Apr 11, 2008 8:59 am

Use coaxial cable. The outside is insulated and the end can be striped to double as the spark gap. It's exactly like a spark plug but without grounded threads and is a lot smaller.
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Spudgun on Crack
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Fri Apr 11, 2008 11:21 am

I have a lot of coaxial cable lying around so i will defiantly be able to use that.

I am going to trying to use the flyback cable as it is smaller but if that doesn't
work i will use the coaxial cable.
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