High Voltage wire

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nexis
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Thu Apr 10, 2008 2:14 pm

I'm working on a new gun for some summer fun. My old guns have had a slow progression into the advancements. First gun was a straight gun with a flint igniter, this one is a over under design with direct propane injection and i hope stun gun ignition.

After poking around and seeing that everyone and his brother is sugesting i use High Voltage wire for the hookup. Before i start digging around in a old monitor i have or ordering the HV wire online, can anyone give me some advice here.

Seems to me that it may be possible to use some old spark plug wires from a car.

Any input here would be greatly appreciated.
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Spitfire
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Thu Apr 10, 2008 3:08 pm

I see no problem with Spark plug wires. They permanently carry high voltage loads. id say go for it
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biggsauce
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Thu Apr 10, 2008 3:18 pm

Agreed, sparkplug wires would be good. Really any high voltage insulated wire is good. Something with some good "meat" to it. 8)
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jimmy101
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Thu Apr 10, 2008 3:55 pm

You really don't need high voltage wire and spark plug wire is not the best choice.

Spark plug wire has very high resistance (couple hundred ohms per foot, compared with generic copper wire at a few milliohms/foot) and it is hard to make sturdy connections to spark plug wire.

You can use any insulated piece of wire, the gauge is unimportant. You can get 1KV probe wire but it is not really necissary. Use whatever insulated wire you have and keep the two wires well seperated from each other and the operator.

Basically you rely on the insulating properties of air, roughly 25KV/inch. As long as the shortest gap is your spark gap the spark will jump there instead of through the wire's insulation.
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Thu Apr 10, 2008 4:11 pm

I use audio wire. It works fine for BBQ ignitors. I have a big spool of it. HV wire is very expensive. The connectors are even more rediculously priced. But if your absolutely sure you need HV wire, you should shop here.
http://www.surplussales.com/Wire-Cable/HVWire-1.html
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Thu Apr 10, 2008 5:21 pm

Seems to me that they are selling Coax cable on there as HV wire. Wonder if you could use the center connector as your conductor
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Thu Apr 10, 2008 6:06 pm

jimmy101 wrote:Spark plug wire has very high resistance (couple hundred ohms per foot, compared with generic copper wire at a few milliohms/foot) and it is hard to make sturdy connections to spark plug wire.
Depends on what kind of spark plug wire you get. Buy the stuff you'll find in normal automotive applications? Yeah, everything you said is true. Buy the racing stuff normally sold hotrodders and the like? Good stuff. Low resistance, blah blah blah.
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Thu Apr 10, 2008 6:27 pm

D_Hall wrote:Depends on what kind of spark plug wire you get. Buy the stuff you'll find in normal automotive applications? Yeah, everything you said is true. Buy the racing stuff normally sold hotrodders and the like? Good stuff. Low resistance, blah blah blah.
Word!

Also, I just make my own. Use some #22 solid core hookup wire, keep your leads as short as possible, and cover each lead with 3 layers of heat shrink tubing all the way into your stun gun housing (nip off the leads protruding out, leave the spark gap inside intact!). On your chamber connections, just use crimp on spade or ring lugs and tighten under your screw heads. Dob the screw heads generously, but neatly, with hot glue.

You may need to use a gradually larger heat shrink for the outer layer.

You can then run it inside a piece of small diameter flexible split tubing to further isolate and insulate if you so desire.
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Thu Apr 10, 2008 6:55 pm

Woyld that wire that come with sprinkler valves work well.
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JDP12
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Thu Apr 10, 2008 6:58 pm

i use 10 gauge solid copper for my hybrid gun, and it works fine
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Thu Apr 10, 2008 7:16 pm

Maniac wrote:Woyld that wire that come with sprinkler valves work well.
It will more than likely be stranded wire, I would prefer solid for this application...too many little pointy ends for the sparks to jump from. If you must use it, twist the ends neatly and tin them with solder...trim the end.
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Fri Apr 11, 2008 12:06 pm

starman wrote:...keep your leads as short as possible, and cover each lead with 3 layers of heat shrink tubing all the way into your stun gun housing (nip off the leads protruding out, leave the spark gap inside intact!).
Short leads really aren't necisary, it doesn't make any difference to the circuit how long the leads are. Of course, short leads will look neater and be a bit easier to keep insulated and separated.

Be careful about removing the external spark points from the stungun. Many stunguns have two sets of external electrodes. The pair with the shorter gap should not be removed. That gap provides a default spark gap and protects the stungun from damage when it is fired without a suitable working gap.

Most stun guns actually have a total of three spark gaps, two external and one internal. The internal gap operates at much lower voltages than the external gaps. To function properly, and to keep the gun from frying itself, the internal and shorter of the two external spark gaps are required.
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