Trouble with spark ignitor - HELP!

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neospudgunner
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Thu Jul 17, 2008 5:49 pm

I haven't had the chance to get any pictures but I took my cannon out just a few minutes ago and now everytime I fire it air comes out the back end. So I wiped off the ignitor and watched the ignitor spark 10 times out of 10, sprayed in the hairspray, and tightened the endcap as much as it would go and it does the same thing. i'm fed up with this bs i'm
p1$$:angryfire:d. This is freaking retarded why wont the freaking thing work!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?
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starman
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Thu Jul 17, 2008 9:17 pm

By "air out the back end" do you mean part of the combustion gases shoot out the rear as well as out of the muzzle? So you are getting it to fire? If combustion is coming out the rear, you just aren't sealing it well enough back there, pure and simple.

Well you are ultimately dealing with spray n pray technology here...these issues are common. Get us some clear pictures of the ignition, clean out cap etc. and maybe we can help you further.
Deadeye
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Fri Jul 18, 2008 10:06 am

Yes Pix would definitely help.
Might be time to saw off and replace the end cap (cleanout).
Add a coupler if you are worried about loosing Chamber length.

Sounds like the ignition problem is remedied, so, one-step closer to success.
nosebleedXD
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Tue Jul 22, 2008 8:30 pm

ROFL WONT A STUN GUN BE WAY TOO POWERFUL and if so, how would you install it?
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SatansEvilTwin
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Tue Jul 22, 2008 9:40 pm

Well ive heard some starter fluid contains oil, and if thats getting on the screws a wire brush wont really get it off. Try wiping them with a cloth
TurboSuper
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Tue Jul 22, 2008 9:57 pm

The problem is that your fuel/air mix is off, plain and simple. It doesn't matter whether you have a 500kV stungun or a small midget in the chamber banging piezoelectric rocks together.

Keep at it- it took me roughly 4 days of experimenting to get it to work, but after a while, you'll get the feel for it.
ROFL WONT A STUN GUN BE WAY TOO POWERFUL and if so, how would you install it?
There's no such thing as "way too powerful" as long as you don't keep your tongue on the electrodes.
Last edited by TurboSuper on Tue Jul 22, 2008 9:59 pm, edited 1 time in total.
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starman
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Tue Jul 22, 2008 9:59 pm

nosebleedXD wrote:ROFL WONT A STUN GUN BE WAY TOO POWERFUL and if so, how would you install it?
No way man. Stun guns are commonly used for a good solid spark ignition. Check out Latke's sitefor lots of details on stun gun ignition.

Both my Clemson combustion and noise cannons both use stun guns very effectively.
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DYI
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Tue Jul 22, 2008 10:38 pm

ROFL WONT A STUN GUN BE WAY TOO POWERFUL and if so, how would you install it?
Stunguns are weak. I shock myself on the arm with one when I'm feeling tired. No, when you're talking about an ignition system being "way too powerful", you should be looking at something a bit more like this:

Image

All basic ignition systems like stunguns, piezoelectric sparkers, ignition coils, and Marx generators are wired pretty much the same way - you get two leads coming from the high voltage source, and you attach one to either end of the spark gap.

As a rough guideline, if your spark is over 10mJ, you're definitely going to achieve ignition in anything but a terrible mix. Basically, if you can see it, it will work.
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nosebleedXD
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Tue Jul 22, 2008 10:42 pm

ROFL SHOCK YOURSELF WITH IT AHAHAHAHA

im guessing its a low powered one o_O

so exactly how would you install a tazer gun

where do you buy it? any cheap ones?

any age restrictions?
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DYI
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Tue Jul 22, 2008 10:51 pm

ROFL SHOCK YOURSELF WITH IT AHAHAHAHA

im guessing its a low powered one o_O

so exactly how would you install a tazer gun

where do you buy it? any cheap ones?

any age restrictions?
Stungun advertising is misleading. All the commercial ones put out more or less the same power. A 1MV potential is pointless if it there's only an inch between the gaps, and maybe 0.5" of clothing between it and your precious nerve endings.

You don't install a Taser, because they're terribly expensive, illegal in most places, and fire darts, which is rather unneccessary for igniting a launcher that isn't trying to run away from you. Stunguns, on the other hand, are quite cheap, but are usually only sold to people over 18 in the States. Anyone can buy one from BCARMS (the Spudfiles store) though.

And if you were referring to shocking yourself with the one above: 16J across the heart can easily be lethal. That thing is 500J. 'Nuff said.
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iisthemuffin
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Wed Jul 23, 2008 12:10 am

This may be a very dumb question, but i see people refer to the term "across the heart" quite often, and i am curious as to what it means.

I assume it has sometyhing to do with the placement of the electricity on your body.
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starman
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Wed Jul 23, 2008 2:36 am

The "across" just means a voltage drop and the accompanying current across and through, well, anything really. You just don't want a lot of it "across" and "through" your heart...too much is a bad bad thing.
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Wed Jul 23, 2008 5:17 pm

iisthemuffin wrote:This may be a very dumb question, but i see people refer to the term "across the heart" quite often, and i am curious as to what it means.

I assume it has sometyhing to do with the placement of the electricity on your body.
Exactly. "Across the heart" is what you would get if you touched one electrode with one hand the other electrode with the other hand. The current flows through the arms and chest and heart and would be potentially fatal.

If you take the stungun and jab it into your arm the current mostly flows through the tissue between the electrodes. There is enough current flow in the arm to contract muscles but relatively little current gets to the heart.

The old adage that you should stand on a hunk of wood when working with household wiring is to prevent a person from creating a conductive path from one hand (touching a hot wire), through the torso (and heart), down a leg, through the shoe and into the ground. A typical 120V, 15 amp household circuit has more than enough power to kill a person in that situation. If you just reached into a circuit and your finger bridged a hot lead and a ground you would get a nasty burn on your finger but little of the current would get to the heart.

Another old electricians rule was to keep one hand in your pocket when working on a hot circuit. Again, that was to prevent creation of a circuit across the chest when one hand touches a hot wire and the other hand touches a ground.
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iisthemuffin
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Wed Jul 23, 2008 7:19 pm

Makes since. Thanks for clearing that up. I had assumed it was sometihng clsoe to that but i had just wanted to be sure.
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nosebleedXD
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Thu Jul 24, 2008 4:55 pm

i think it would be a waste of a stun gun
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