Stun Gun ignition problem

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kellon17
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Wed Jul 23, 2008 1:36 am

Hey guys! I'm working on my first gun and it's an advanced combustion. I just finished wiring up the stun gun to allow for 2 sparks. My problem, however is that the spark is arcing very inconsistently across the electrodes. It will arc across the default gap most of the time and then every now and again it will fire at the electrodes. The gaps are no more than 1/4". What do you guys think? Image

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starman
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Wed Jul 23, 2008 1:46 am

Does it have a fresh battery? You shouldn't have any inconsistant firing across the default gap. When it's connected to your chamber gap there so be no spark at all at the default gap...only over your chamber gap.

1/4" should be fine.

Edit: OK your pics are up. Your HV wiring is very scrambled on the outside and I believe there is a reasonable degree of possiblity you spark is jumping between the cables.

AND the screws forming your middle gap are way too close to each other where they enter the chamber..this is a serious problem and needs to be corrected. Actually this gap could even be smaller than both of your gaps inside...they are adding up to way more than 1/4"...more like 3/4" to 1"...causing your spark inconsistancy in the chamber.
kellon17
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Wed Jul 23, 2008 2:16 am

Thanks for the quick reply man! I realized after i drilled the first two holes (the ones on the left in the picture) that they were way to close. That was a stupid mistake on my part. So what I was thinking about doing was just scrapping that spark and leaving those two screws in there. What about if I just ran it with the one spark?
I just did a little trouble shooting and I figured out that if I detach the wires from the two electrodes that are closer to the barrel and I put those wires close together, then the spark fires b/t the electrodes closer to the back of the gun and in between the two wires up front. Thus discontinuing the fire b/t the default gap and working like it is supposed to. But then, when I attach those wires back to the electrodes, the spark returns to the default gap. I realize my wires are crazy, I'm going to clean all that crap up when I get it working properly.
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starman
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Wed Jul 23, 2008 2:25 am

You could just abandon one screw and install a third one further around and keep your second gap. It will work with only the one gap up front but possibly not as consistantly. Having both the middle gap and the front one will be better.

Also, close your gaps way down to 1/8" or so each. The spark won't be as pretty but it will do the job just as effectively and be more reliable.

Clean up your cabling taking as short a route as possible and not criss-crossing each other.
kellon17
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Wed Jul 23, 2008 2:32 am

So do you think I should put another screw closer to where the meter enters the chamber? And then attach the wire with the blue heat shrink to that one? But then there will be a screw in the middle that is just chilling there. Would that cause problems? Or should I put another screw more towards the propane holder and attach the wire with the black heat shrink to it?
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starman
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Wed Jul 23, 2008 2:45 am

No, install another screw more behind the stun gun and abandon the screw with the black heat shrink. Back that screw out and cut it off short so it doesn't interfere with your gap. Replace it in its hole as a filler plug. [SEE BELOW]

Then, disconnect all your HV wires and do this...

- connect the top stun gun terminal straight out to the top left spark screw

- connect the bottom left spark screw straight across to the right bottom spark screw

- connect the top right screw back over to the other stun gun terminal

Make sure your gaps are close, using longer screws if you need to. Should spark for a lifetime.... :wink:

EDIT: Actually no. You had better take the middle screw out completely and plug the hole with epoxy. I'm afraid it might still cause a spark bridge there.
kellon17
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Wed Jul 23, 2008 4:00 am

Good deal! All I did was move that screw and it's golden now! I'm a little worried about the epoxy keeping all that combustion from exiting through that small hole but hopefully it will hold. Thanks a ton! First fire will be later today.
sirspuddest
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Wed Jul 23, 2008 5:28 pm

You really don't have to worry about whether or not epoxy will hold. I'm sure it will hold up just fine.
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