CAPACITOR DISCHARGE EXPERIMENTS:

_____________________________________________________________
DISCLAIMER: the experiments described below are fantastically
dangerous, and they are described without reference to the 
many precautions needed to guarantee the experimenter's safety.  
Accidentally discharging these capacitor banks through your 
body can not only kill, but can explode flesh and bone. 
Exploding water can launch electrode fragments at high velocities.  
The watergun is a full-fledged cannon, and must be treated as 
such.  And these are not the only hazards. I describe these 
experiments for your information only.  Anyone who attempts
to duplicate them does so at their own risk.  And the risk
is considerable unless you know EXACTLY what you are doing.
-------------------------------------------------------------


THE "WATERGUN"

by Bill Beaty, experiment by Dan Y. and Dale T.

The capacitor discharge gun was a 6" cylinder of mild steel, 2" 
diameter with a 1/2" hole bored most of the way through axially.  
At the base, two holes were bored in from the sides and threaded 
to take standard sparkplugs.  The gun was fired at up to 40KV 
from a bank of six 3uF capacitors (about 1/2 cubic yard in size!) 
using 1-1/2" x 1/2" copper busbar as conductors.  The switching
gap was a pair of metal spheres between which a short length of metal
rod was inserted using air pressure.  About one cm^3 of water was 
placed in the gun, and a steel ballbearing was initially used as 
the projectile.

In the initial tries, the sparkplugs blew out violently from the
gun, and the ballbearing was gently lofted from the barrel.  We assume 
that the force originates in the discharge gap, and so we need to 
position the gap closer to the base of the barrel.

The sparkplugs were replaced with turned teflon rods and copper wire
conductors, with the single discharge gap centered in the barrel.  The
ball bearing was replaced with a black polyethelene cylinder with flat
ends, which gave a slip fit into the bore.  A clay cube of about 10" to
12" thick (water based modeling clay) was used as a target.  When fired, the
teflon rods and the copper conductors were still blown out of the holes. 
But this time the slug went through the entire clay block, leaving a large
entrance hole and a tiny exit hole.  The entrance hole was conical, with
ripples and spirals on the walls.  Amazingly, the projectle had not the
slightest bit of damage, and the edges of the beveled end were even still
sharp and polished.  Even more amazing, after going through the entire
block of clay, the slug was stopped by the thin poly bag that covered the
back of the clay block.


5/95 - In the spring issue of ELECTRIC SPACECRAFT JOURNAL, the Richmond 
Virginia Tesla Coil Builders Assn. have an article on their own watergun 
experiments.  They manage to perforate a 1/4" aluminum plate with nothing 
but the water projected from the end of the gun.  They attempt to look 
for anomalous energy production, but their results are inconclusive.

Some references recommended by Tom Coradeschi

IEEE Transactions on Magnetics:

Vol. MAG-18, No. 1, January 1982
     1980 Conference on Electromagnetic Guns and Launchers 
     
Vol. MAG-20, No. 2, March 1984
     2nd Symposium on Electromagnetic Launch Technology
     
Vol. MAG-22, No. 6, November 1986
     3rd Symposium on Electromagnetic Launch Technology
     
Vol. 25, No. 1, January 1989
     4th Symposium on Electromagnetic Launch Technology
     
Vol. 27, No. 1, January 1991
     5th Symposium on Electromagnetic Launch Technology
     
Vol. 29, No. 1, January 1993
     6th Symposium on Electromagnetic Launch Technology
     
Vol. 31, No. 1, January 1995
     7th Symposium on Electromagnetic Launch Technology

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SOME CAPACITOR EXPERIMENT RESULTS,                          7/10/94
or,  Blowing Stuff Up: a "guy thing"

We tried discharging through small pieces of agar gel with various electrode
lengths and spacing.  Capacitor bank: three 100uF, 30KV units in parallel.  
Switching gap: two 1-1/2" brass spheres moved by an AC solenoid, with
flexible contact made via several flat 1" ground braids.   8" lengths of 
heavy solid copper wire (#12?) were run from the capacitor terminals and 
were bent to form a gap, into which small blocks of agar were placed.  A 
styrene cottage cheese bowl was placed below the gap to shield the capacitor 
conductors from agar splatter.  A 12" Tupperware bowl was placed over 
the gap to shield the rest of the room from flying agar.

At low voltage (under 2KV) there was no explosion.  Instead, the agar glowed 
yellow, sputtered, and melted adjacent to one electrode wire.  This is 
similar to the "glowing 120V pickel" demo, where an arc burns pickel flesh 
from around an electrode with a crawling arc which sequentially attacks 
the material closest to the electrode.

With electrodes inserted 1/2" into the agar at 1" spacing and 2.5KV, there 
was an extremely loud blast which shattered the styrene cottage cheese bowl 
we had placed below the wires in an attempt to shield the conductors from
agar splatter.  But even with a blast like a shotgun discharge, the agar 
simply broke into several pieces and fell from the electrodes.  The 
explosion was all sound, but with very little mechanical force.

With 1/2" electrodes at 1/4" spacing, the blast was extremely loud, the
agar was thrown out from the discharge as a liquid spray, the cottage
cheese bowl was again shattered and blown downwards, and the 10"
tupperware bowl that covered the assembly was shattered!  Bill thinks it
happened not only from overpressure, but from fast risetime of force which
shattered the plastic like sillyputty with a hammer.  Because the agar was
splattered on this run, we suspect that the voltage and spacing in the
previous run must have been just at the explosion-producing threshold. 
Also note that the explosion energy seems to be nonlinear with respect to
e-field, and with respect to total input energy since reducing the gap
while keeping capacitor voltage and capacitance constant seems to have
enormously raised the energy output.  Perhaps energy is proportional to
peak current? Or perhaps there is a threshold in voltage or current below
which explosion energy falls rapidly. 

Since the discharge is intensely loud, Bill suspects that the extremely
loud noise from the quartershrinker^* setup may be coming from the 
switching gap, and not from the exploding coil.  After all, covering the 
quarter with the iron pipe did not reduce the noise all that much.  Dr. 
P. Graneau has written about anomolies with high current air arcs, 
pointing out in particular that the sound from lightning may not simply 
be from thermal transient air expansion, but from unexplored plasma 
dynamics which produce shock waves via motor effects.  Perhaps this is 
the source of the intense sound from the discharge.

 *
  Quartershrinker: device which electrically compresses a coin
   into a small, shrivled, spherical lump.  See EXTRAORDINARY
   SCIENCE, Vol 5 No.3, Summer 1993, p10 (pub of the Intl. Tesla
   Society, Colorado Springs, CO, 719-475-0918.  Email the author
   at ghawk@eskimo.com, or http://www.eskimo.com/~ghawk


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IDEAS FOR THE FUTURE:

Place a glob of jello against a solid sheet (metal, plastic, etc.)
Stick capacitor wires in the jello.  Fire the capacitor.  Will
the exploding jello shatter or dent the plate?  Place it against
a coin.  Will it cause dents?  Can exploding jello drive a quarter
into a block of wood?

Obtain a satellite TV dish.  Suspend a jello-glob blaster (as above)
a little farther away than the dish focus.  Find the distant
secondary focus optically, and place objects there.  Fire off
the capacitor, and see if the refocussed blast wave can do damage
at a distance.  Blow out a candle at fifty paces?  Shred a roll
of toilet paper?  Atmospheric lithotripter!

Measure the output energy of the capacitor discharge.
"Free energy" test: fast, high current impulses tend to do weird 
things.  Are they a F/E source? Discharge the capacitor many 
times in a container of water.  Measure the temperature increase, 
and calculate energy input.  Calculate electrical energy use.
Is it anywhere near unity?  Is it over unity?  Fire a supergun
upwards with a heavy bullet, measure the height.  Fire it into
a ballistic pendulum, measure the height.  

Coil-crush a quarter inside a heavy pipe full of oil.  Is coil still
destroyed?  (Put it in a big baggie to limit the mess)

Blow a bare coil inside a cup of water.  Anything interesting happen?
Is explosion symmetrical, or do water jets form?  Is there a difference
between fresh water and electrolyte?

Drill a 1/2" depression in a metal block.  Fill it with water.
suspend a wire that touches the center of the water.  Discharge
the capacitor between block and wire.  Is safety shield needed?
Maybe not, and the plasma jet will be easily observed.  Try
different sizes of holes.  Try a deep hole with a drop of water in the
bottom and a long conductor making contact. Direct the jet against 
various materials.

Run the capacitor leads to a baggie of water.  Fire it off, and
make a mess.  Do it with paint in a parking lot, maybe several
colors and various objects to make blast shadows.  A big blast
with manniquins against a wall makes "Hiroshima" effects.

Fill a flexible (rubber?) container with water, insert capacitor
leads.  Try firing it with low voltages, see how high a voltage
is needed for explosions.  Try firing it with various electrode
separations.  What exactly is needed to make water explode?

Install a heavy polycarbonate window on the above rubber bucket, and
observe small water explosions underwater.

Discharge a capacitor bank through the ground, while using geophones
to listen at great distance.  How far can the sound be detected?
Instead, use electrodes and an audio amp to listen at a distance.
How far away can the EMF effects be detected?

Can "machinable ceramic" stand up to water blasts?  If so, make a
reusable cannon: Bore a large hole most of the way through a 2"
metal bar.  Bore a much smaller hole the rest of the way.  Carve
a thick disk of ceramic that slip-fits into the large bored hole.
Drill a hole through the center of the ceramic disk.  Machine another
electrode in the shape of a giant nailhead.  Stick this through
the ceramic disk, so the shaft of the "nail" extends out the back
of the cannon, and the ceramic separates the center electrode from
the metal cannon.  Put a little water in the cannon, and discharge
the capacitor between the cannon and the center electrode.  If the
ceramic can take the shock, the device is reusable.  If a small-
bore cannon with lots of water is used, the slug of water itself will
become the projectile.  P. Graneau claims that such a waterslug can
penetrate a 1/4" aluminum plate.  But how big a capacitor bank did
HE use?
              ___          ___
             |   |        |   |                 
             |   |        |   |                 
             |   |        |   |                 
             |   |        |   |                 
             |   |        |   |                 
 ASSEMBLED   |   |        |   |                 
  CANNON     |   |        |   |                 
             |   |        |   |                 
             |   |        |   |                         CENTER
             |   |        |   |                        ELECTRODE
             |   | ====== |   |           CERAMIC       ======
             |   | ==||== |   |          ___   ___        ||
             |   |+++||+++|   |         |+++| |+++|       || 
             |   |+++||+++|   |         |+++| |+++|       ||
             |   |+++||+++|   |         |+++| |+++|       ||
             |    \++||++/    |         |_++| |++_|       ||
              \____|+||+|____/            \_| |_/         ||
                     ||                                   ||
                     ||                                   ||
                     ||                                   ||
                     ||                                   ||



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MORE STUFF:

F/E testing: discharge in a calorimeter repeatedly, maybe use sorbothane
packing around sphere electrodes, see if T(rise) is anomolous.  Underwater
discharges are probably too destructive to containers

Discharge underwater with plastic or wax lenses to refocus the shockwave and
destroy objects at the lens focus.

Place a small water drop on a metal block, touch the drop with a metal
wire, connect the block and wire to the discharge capacitor.  Is the
block surface damaged?

Try inducing long discharge paths using wet thread, the thinner the better.
Will curved thread cause shockwave focusing effects?

Wrap wet string around a thin plastic tube, place a quarter inside.
Perhaps the discharge will form a spiral arc with good conductivity
which will warp the coin without requiring the destruction of a copper 
coil?

Try graphing sound peak amplitude versus capacitor voltage for a constant 
length short arc.  Force an arc initiation at all voltages by using wet 
filaments or #40 wire across electrodes.  Is sound proportional to voltage,
energy, or what?  If more than proportional to energy, F/E is revealed?

Are water-arcs different from other arcs?  Run some very thin wire to a
tiny block of jello and fire it off.  Does the exploding jello give a
different explosion pattern than the exploding wire?

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