No spark with camera ignition

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Lurwah
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Sat Mar 24, 2007 7:39 am

Hi!

First off: Sorry if this has already been discussed, I've searched, but I couldn't find it anywhere.

I'm currently trying to upgrade my first spudgun with a camera ignition, but it won't work! So far I've used those long-nosed lighters, but they always broke ( literally ), so I got fed up with them.

My ignition right now consists of:
- a capacitor ( and everything else it was connected to inside the camera )
- 2 switches ( one for charging, the other for firing )
- 2 screws ( with tiny nails soldered on the tip )

I took out the flash, connected the 2 +/- wires to the screws and placed the screws less than a millimeter apart, but there's no spark. The only way to get a spark is to hold the firing switch and touch the screws with a screwdriver ( and than it works brilliantly! ).

I've also tried holding the third wire close, but that doesn't make any difference.

I'd really appreciate your help.

P.S. I'm Dutch, not really bad at English, but any comments on spelling and grammar is greatly appreciated, always looking for improvement ( with speech and spudguns :) ).
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Hotwired
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Sat Mar 24, 2007 8:03 am

If you want it to spark it needs to be REALLY close, a fraction of a millimeter.

The third wire has to be in a loop or hoop around the two nail tips, not touching anything, so that when you press the button it ionises the air around itself and makes it possible for the spark to jump between the two nails.
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CpTn_lAw
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Sat Mar 24, 2007 8:07 am

can you post a picture of your setup? cause i've had the same problem with my first combustion, and i solved it...so please send a detailed picture, i'll work on it to improve it.
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Lurwah
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Sat Mar 24, 2007 8:21 am

Thanks for the quick reply!

Does the third wire need to be as close as well? Because I don't want to work with wires outside my box ( the isolation melts and stuff ) and I don't think I can bend hard metal in such a small loop.

Edit: I haven't got my camera right now, maybe later today.
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FeLeX
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Sat Mar 24, 2007 9:31 am

Your two wires (+,-) have to be coming from the lamp that flashes. Desolder the lamp and solder the wires onto where the lamp was and then put them close together (1mm away like Hotwired said). The third wire is totaly not required at all but it does prolong the life of the unit. Hope that helped ya!
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Lurwah
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Sat Mar 24, 2007 9:39 am

FeLeX wrote:Your two wires (+,-) have to be coming from the lamp that flashes. Desolder the lamp and solder the wires onto where the lamp was and then put them close together (1mm away like Hotwired said). The third wire is totaly not required at all but it does prolong the life of the unit. Hope that helped ya!
Well, I already have that, and it doesn't work. And now I'm really getting confused about the third wire :? .
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FeLeX
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Sat Mar 24, 2007 9:46 am

The third wire is for the flourescent lamp, dont worry about it. Does it make sparks if you manualy zap it? Because if it doesnt that means your unit is burned down.
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Lurwah
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Sat Mar 24, 2007 9:50 am

Lurwah wrote:
I took out the flash, connected the 2 +/- wires to the screws and placed the screws less than a millimeter apart, but there's no spark. The only way to get a spark is to hold the firing switch and touch the screws with a screwdriver ( and than it works brilliantly! ).
So: Yeah, my unit still works. I'll have my camera tonight, maybe some pictures will help.
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FeLeX
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Sat Mar 24, 2007 9:55 am

http://www.spudfiles.com/forums/viewtopic.php?t=4611
Look at that maybe it will help you.
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Lurwah
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Sat Mar 24, 2007 10:38 am

OK, update.

I made a loop of metal wire around the the two screws and connected the third wire to the loop, the loop and the two screws were very close, but not touching.

There was one ZAP while I was still charging 0_0 ( that shouldn't have happened ) and it did nothing afterwards.

I already looked at the link posted by FeLeX before posting myself, but since holding the third wire close didn't do anything, I decided to ask.

So, I still need help... :(
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FeLeX
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Sat Mar 24, 2007 10:44 am

Thats so weird =/ I did mine long ago and it still works fine. You gotta post some pics. Maybe then we can help.
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Fnord
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Sat Mar 24, 2007 11:00 am

It takes 10000 volts to jump one cm at normal air pressure. Those capacitors hold 500-600 if you're lucky.
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FeLeX
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Sat Mar 24, 2007 11:04 am

Who said anything about cm? The cap in the camera has 230 volts. 1mm gap.
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Fnord
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Sat Mar 24, 2007 11:15 am

If you do the math youll see that 230 volts will only jump .23 mm. I figured that would be obvious but I guess not.
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FeLeX
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Sat Mar 24, 2007 11:38 am

Lol yea after I posted I was like WTF was I thinking. I used old spark plug and bent it to have very small gap, almost touching, worked fine.
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