spark in steel chamber

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singularity
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Wed Apr 25, 2007 5:58 pm

im working on a cannon that runs on hydrogen, but i have ran into a problem. the only pipe that could possible wistand a hydrogen blast safely is steel. what is the best way to put a spark gap in a steel chamber without it just shorting all the voltage through the pipe. my chamber is very small (3/4 by 3) so it needs to be small and simple. im thinking i should ground the pipe and just have the spark jump to the side of the pipe but im not sure.

basically im asking for the simplest and most effective way to put a spark gap in a metal chamber
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iknowmy3tables
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Wed Apr 25, 2007 6:21 pm

I'm wondering the same thing, all I can think of is a extra thick pvc section made from solid pvc
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chaos
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Wed Apr 25, 2007 6:38 pm

use non condutive washers, insulated wire, and non contuctive steel putty like seen on another thread.

oh and the leads* from bbq peizo sparkers come with insulated probes
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turbohacker
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Wed Apr 25, 2007 6:44 pm

make something that has both contacts attache to the wires and then just throw it in-
be carful with hydrogen
also dont inhale hydrogen thinking that it will have the same effects as hilium because it is five times lighter, not that i know that fom experience or anything-cough cause i dont-cough-cough
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singularity
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Wed Apr 25, 2007 7:17 pm

dont inhale hydrogen thinking that it will have the same effects as hilium because it is five times lighter, not that i know that fom experience or anything-cough cause i dont-cough-cough
that was wicked discrete

any way i was thinking if i sleeved a bolt in some small flexible plastic tubbing and some plastic washers and use that as a probe, then ground the pipe that would make it spark from the probe to the wall right?
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Kenny_McCormic
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Thu Apr 26, 2007 5:26 pm

they make very small sparkplugs for chainsaws and stuff that might fit
cerberus
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Thu Apr 26, 2007 5:37 pm

If you used the sleeving approach you might have trouble keeping everything in place during combustion. You'd probably have more luck drilling a small hole through the center of a bolt and passing a length of HV wire though the hole then as you say, ground the chamber. Check out http://www.advancedspuds.com/nosparkplug.htm for a better description of what I'm talking about. You may want to use a longer bolt though so that the spark is closer to the center of the chamber.
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schmanman
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Thu Apr 26, 2007 5:51 pm

a spark plug! :wink:
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cerberus
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Thu Apr 26, 2007 6:15 pm

Yes, but a homemade spark plug that can be made to any size you desire.
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schmanman
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Fri Apr 27, 2007 5:33 am

no, thread in a car spark plug.
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frankrede
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Fri Apr 27, 2007 6:55 am

turbohacker wrote:make something that has both contacts attache to the wires and then just throw it in-
be carful with hydrogen
also dont inhale hydrogen thinking that it will have the same effects as hilium because it is five times lighter, not that i know that fom experience or anything-cough cause i dont-cough-cough
Inhaling hydrogen sounds so damn dangerous.
Imagine if you had a spark in your lungs!
Now taht probably will never happen, the results would be devastating!
Current project: Afghanistan deployment
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meatballs
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Fri Apr 27, 2007 6:10 pm

does it have to be an electrical spark or could you use a lantern sparker or similar device. then you wouldn't have to bother with a grill ignitor, or as you were planning, an engine coil. or go with the spark plug idea. does epoxy conduct electricity? and is there some way to have a spark gap inside the cannon with two insulated wires going in? or have the chamber be grounded and have an insulated wire going into the cannon? or what if you cut a tiny hole and used a fuse? that would be awesome, like a real cannon.
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Fri Apr 27, 2007 7:34 pm

or even better a dirtbike spark plug! you can find one at any local motorsports store. its just a thought though. and i bet its cheaper than a car spark plug unless you have one laying around.
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meatballs
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Fri Apr 27, 2007 10:48 pm

or, better yet, you could use a pocket bike spark plug. Cody probably wouldn't notice if one of his cylinders wasn't firing.
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frankrede
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Fri Apr 27, 2007 10:51 pm

If you can't figure out how to make a simple spark in a steel chamber, why should you be playing with hydrogen?
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