Although not an ion gun per say...plasma gun.

[3l]

Hi Mark:

really a plasma.
It lasts due to the leidenfrost effect.

Happy Fusoring!
Larry Leins
Fusor Tech

[Adam Szendrey]

This thing could be scaled up. A MOT (or more MOTs in paralel) can provide a massive arc to be fired. With a 30-40 kV, 5-10 uF cap bank this could be a really neat burgler annihilator .
Or attach it to the roof of your car. Mad Max frenzy.
Anyway, i think i'll try this one day. For some reason, building destructive things has it's beauty.
Like a nuclear bomb...you can hardly ever see such a beautiful , and magnificent explosion. You can feel the power.
Yet, it is capable of killing millions of human lifes.

Adam

[Q]

i have to agree. it's like a tesla coil, you build it, and it makes really nice sparks... but what do you do with it?
then people ask why you built it... "because i wanted to"
there is just something about a powerful discharge.

this one is a project that i have almost finished.

Q

[Mark Rowley]

Q, try to post some pics when you get it done.

Mark Rowley

[3l]

Hi Guys:

I forgot to mention that to get really long lasting arcs you need an ionoizing agent like aquaous lithium chloride or Bromide.
Use strontium chloride for bright red.
Barium chloride for bright green.
I used 10 grams in a 2 cup measuring cup of deionized water.
I used a lantern wick to feed it in ...it is self regulating...it burns away.

Happy Fusoring!
Larry Leins
Fusor Tech

[apollo]

How long do these things last? How far do they go?
How often do you need to replace the carbon rods?
Where do you put the ionizing agent?
So really all this device does is put an arc from a capacitor in between the two carbon rods? It doesn't pre-ionize the air first?

[3l]

Hi Liam:

The wick goes into the center of the arc.
A 6 " wick will last a month of continous firings.
A Coalman Lantern wick will do.
The idea is to get a hot broad spark between the electrodes.
I can usually pull the rods 3 " apart while making an arc.
In 3 years of running the carbons never needed replacement.

Happy Fusoring!
Larry Leins
Fusor Tech

[Mark Rowley]

Larry,
So this Strontium or Bromide acts as a medium for the plasma to operate in ? This sounds quite similar to microwave oven plasma. In the microwave, the plasma uses a medium of carbon(ie. smoke) to operate in. Is this a correct assumption ?

From reading your post it seems that this will not work without these mediums.

Mark Rowley

[3l]

Hi Mark:

It won't last more than four feet without the ionizing agents.
These agents when ionised perpetuate the plasma for a few seconds more so you can get more height.
The longest fireball time is 3 seconds at 100 joules.
They never hit the ground unless they hit something to reflect them like a power line!

Carefull Yall these things take no prisoners if they happen to hit dry leaves or a stack of newspapers or trash pile.

Happy Fusoring!
Larry Leins
Fusor Tech

[shojidoug]

Do you think you could magnetically or elctrostaiclly capture one of these plasma balls?
Then mabey "feed it" to keep it up and running? Just a fun thought

[Brian McDermott]

Maybe feed it with deuterium. Would you get sufficient maxwellian heating for fusion with a big enough pulse?

[Adam Szendrey]

I strongly doubt that this would work. . I don't think that a simple 330 or 170 V (regulated mains) arc would be "hot" enough for fusion.
Anyway, this is what tokamaks are doing at large scale (if i recall correctly, they even used high power discharges to heat up the plasma, but the ions are not created via an arc), but there the temperatures (or ion energies) achieved are much higher.
As said many times, the fusor is much more efficient, as it directly collides deuterons.
In a tokamak, the ions collide in all directions, and just a very small percentage does that head-on. A lot of energy wasted.

Adam

[Brian McDermott]

I was thinking of the Z-Pinch device when I wrote this, as it uses high energy discharges to heat a plasma to high temperatures and get fusion. The magnetic field is merely a product of the electric current that flows through the plasma. Now that I think about it, the plasmoid in the accelerator device is at atmospheric pressure, so mean free path would probably be too low.

[Q]

here's a thought, make a coaxial version of this thing.
it might be somewhat like an atmospheric spheromak...

Q

[shojidoug]

Fusion at atmospheric pressure's might be impossible, but the experience gained from trying to manipulate a plasma ball in open air conditions without time consuming and expensive containment and vacuum might be directly utilized in fusion experiments not to mention the eureka factor from accidental discovers. Besides it sounds like a lot of fun, so I ask again
How would you capture and keep it alive?

[Starfire]

Capture is easy - use an inverted glass or ceramic bowl. Keeping it alive is another matter.

http://jlnlabs.imars.com/plasma/gmrtst/index.htm

http://www.abc.net.au/science/news/stories/s520317.htm

[Q]

well, for this project i'm not trying to cause fusion, nor really come up with anything immediately useful. it just sounds fun. you know, a nice ball of plasma rocketing up into the air for a few tenths of a second. : )
though the expiriance could definately be useful later on.

Q

[shojidoug]

Going through the early post on this subject I found this little tidbit by the esteemed Larry Leins "They never hit the ground unless they hit something to reflect them like a power line!"
So it would appear that something as simple as 3 rings charged with AC current arranged in a globe type configuration (2 smaller ones on the ends one larger in the middle) might be enough to hold it steady, that gives you 3 seconds to pump it with something before it dies maybe a stream of plasma containing the enhancing agents he talked about earlier or maybe E.M.P. would be enough. Any one else have any ideas?
Thanks
Doug

[Mark Rowley]

I just recieved the book today. It only has a quick reference to this topic. It specifically points to a 1963 article by Scientific American titled "Shock Waves and High Temperatures. The article was written by Malcolm McChesney. Maybe with a little digging, someone can unearth this article.

BTW, I recommend the book( Termperatures Very Low and Very High). It covers just about everything in thermodynamics and provides diagrams of many different related(and obscure) devices. The last chapter titled "Beyond Infinity to Negative Temperatures" is especially interesting.

Thanks again Larry for book reference !

On the capturing and feeding of these plasma balls. Prior to my fusor endeavor, I was experimenting quite a bit with the microwave plasma phenomenon. I was able to capture the balls in pyrex jars and keep them going for 30 seconds. Beyond that, I usually had containment failure(glass shattering). I found that a continuous feed of carbon(smoke) would keep a MW Plasma alive for a long time. However, this required the plasma to constantly be saturated with high energy MW's. As soon as the MW power is shut off, the plasma instantly evaporates. As a result, I would doubt that the Leidenfrost Effect is in play here as it is with the plasma gun. From what I can now see, I dont think there are many similarities between the MW plasma and the plasma from this gun design.

Being that this plasma gun creates something of a much greater temperature(500,000K *per the book), I am not sure how long you could keep it going w/out containment failure. Maybe if the ball was shot vertically into a bell jar pumped full of a gas medium it would last longer. Very interesting project.

Mark Rowley

[steffan]

Can the mains arc be substituted by a neon sign transformer?

[apollo]

Hi there
You made reference to a wire suspended 1/2" below the arc. Did you forget this on your diagram? Also, how many volts should it be, and wouldn't it be more efficient to use one or two good magnets, positive side up?
-Liam Bowen

[3l]

Hi Liam:

That wire creates a mirror magnetic field that does the actual repulsion. To get a really good result the discharge voltage should be at least 2kv.

Happy Fusoring!
Larry Leins
Fusor tech

[dmills]

Sounds like a job for a Compulsator (compensated pulsed
alternator). These also look kind of cool for a Z pinch rig.

Serious current pulses from stored kinetic energy!
Just remember the reaction torque on the stator when the thing
is triggered!

http://www.utexas.edu/research/cem/prog ... ed_ac.html

Just dreaming!

Regards, Dan.

[gopher]

So... has anyone yet constructed this device (besides Mr. Leins)? If so, please share the results!

[Q]

i did, but i was not successful. i kept having mechanical issues with the carbon electrodes... i couldn't find a way to keep them secure. so, i got some nice arcs, but every time i discharged the cap, the electrodes would be blown out of the device.
i donno, is a .15uf 35kv cap to big?

Q