Is your town full of rednecks and hippies? Do you get dull stares when
you ask around town for "carbon fiber veil"? Of course, carbon fiber veil is
probably the best material yet discovered with which to create microwave
oven ball lightning, but the harsh reality is that carbon veil is still a
somewhat exotic material to obtain. I got my supply from Boeing Surplus in
Kent, Washington, which is only about 20 minutes south of where I live here
in Seattle. About 20 minutes north of me is one of the nation's best
suppliers of composite materials: Fiberlay. Unfortunately, Boeing Surplus
does not regularly carry carbon fiber veil, and they are not set up for mail
order operations as far as I know. Fortunately, Fiberlay does have a mail
order service. But what if you are really impatient, like me, and want to
make ball lightning RIGHT NOW? Well you are in luck, for one can make ball
lightning in the old microwave oven using steel wool. So even if your home
town is full of gun racks and Birkenstocks, you can still experience the
miracle of cutting-edge plasma physics!
First, let me cover the basics for all those readers who have never
seen or created ball lightning in the microwave oven. There are numerous
materials and shape configurations that have been used to create this
effect. I have tried the following: carbon fiber veil (the very best),
carbon arc welding rods, graphite mechanical pencil "leads," carbon fiber
from woven cloth, carbon fiber tubes, graphite powder, burning candles,
charred toothpicks, aluminum foils and sheets, copper foil, copper wire,
copper scouring pads, solder, and steel wool. Of all of these, only carbon
fiber veil and steel wool work consistently. This is why I am writing this
essay; you can find all kinds of methods and materials with which to create
ball lightning all over the Internet, but of those I have tried only two
work consistently. (For information on the King of Ball Lightning methods,
google "Bigger, Better Balls.")
To create ball lightning using steel wool, you should use the finest
steel wool available, which is 0000 (which everyone calls quadruple "aught,"
but which should be called quadruple "naught," for aught means "something"
or "everything" whereas naught means "nothing" or "zero"). I have been able
to make 000, or triple naught, steel wool work, but I suggest you stick with
0000. You will need a microwave oven with enough power to make this effect
work. Opinions vary among researchers, but the consensus seems to be that at
least 1000 watts is needed. Most new microwave ovens are at least this
powerful, but some of the tiny ones may not be. What if you have an old oven
and you don't know how powerful it is? If you check the back of the oven you
may find a plate listing the serial number and other manufacturer data. Look
for a number indicating the amount of current being drawn by the machine in
amperes or "A." Multiplying this amperage by 120 volts will give you the
wattage. But remember, this is the amount of power drawn by the machine, not
the amount put out by the magnetron. My oven draws about 1700 watts but is
only rated at 1250 watts. So the power drawn by the machine is really only a
rough guide to its rated power. You may be able to find the power rating of
an old machine simply by doing an Internet search on the brand name and
model number. This method worked for me, although I am fastidious enough to
have saved the owner's manual!
You will need a glass bowl to act as a "bell jar" to contain the ball
lightning once it erupts from the steel wool. You can use any glass
container, but I highly advise you to stick with brand-name Pyrex "bakeware"
or at least glassware that is designed to hold food for baking in a
conventional oven. Most second-hand stores have loads of glassware. The
reason for using bakeware and not ornamental glass (fishbowls and the like)
is heat. Once formed, the plasma has a tendency to get very hot very
quickly. This brings us to the most important safety aspect of the whole
demonstration: Once you have created the luminous ball, NEVER RUN THE OVEN
FOR MORE THAN A FEW SECONDS. Note that a few seconds means like 2 or 3
seconds! I speak from experience when I tell you that glassware can and will
shatter when exposed for any length of time to hot plasma. I can only
conclude that plasma is a really good absorber of microwave energy because
it gets so hot so quickly.
The last item you will need is some sort of heat resistant stand or
block to elevate the steel wool off the floor of the oven. The easiest to
use is probably a small ceramic ashtray. Second-hand stores have lots and
lots of ashtrays. There are a couple of reasons for this seemingly trivial
addition. First, you will get much better results in general if you remove
the revolving glass platter and plastic lazy Susan bearing before the demo.
This leaves a bare metal "floor" and you will either get no ignition or an
arcing electrical discharge to the floor if you simply set the steel wool on
the floor. Second, the floor, ceiling, and sides of the oven act as
reflective surfaces for the microwave energy and make poor places to
position things if you want them to get hot. Elevating anything off the
floor gives it a much better chance to get hot. Also note that "stoneware"
(such as small candle holders) is not the same as ceramic. Stick with white
ceramic ashtrays or cups and avoid glazed stoneware and glass ashtrays.
So here we go: First, remove the revolving glass platter and lazy Susan
bearing from your oven. Notice that this leaves a "trough" or circular
depression between the center spindle and the outer corners of the oven
floor. This is good, as it creates an air gap when bridged by the overturned
bakeware bell jar. The air gap allows the strong acoustic buzzing of the
plasma to escape under the glass. If you set the bakeware over the steel
wool without leaving a gap, you will get a strong glass-on-metal buzzing or
rattling sound that detracts from the elegant beauty of the demonstration.
Place the ashtray in the oven. It can either be right-side up or upside
down. Upside down might work a little better because it is slightly more
elevated and the walls of the ashtray will not obscure the sightlines to the
Place a walnut-sized blob (2 cm in diameter) of 0000 steel wool in or
on the ashtray. Cover with the overturned bakeware. Obviously the bakeware
needs to fit over the ashtray. This is usually not a problem, but it is
worth checking the fit when shopping at the second-hand store. Make sure the
bakeware bridges the lazy Susan trough and creates an air gap.
Because very fine steel wool will ignite with just a match, you should
have a glass or bowl of water handy to dunk glowing steel wool in after the
demonstration. Don't just throw it in the garbage or recycle can!
Close the oven door and set the oven to full power. How much time you
set it for does not really matter since we will only run it for a few
seconds. Opening the door automatically shuts off the oven, so as soon as
you push the Start button move your hand to the "open door" button.
Once you push the Start button, the effect should occur almost
immediately. The steel wool should begin to glow red, then white, and then
the plasma will jump up from the steel wool and "flow" around the underside
of the glass container. The great temptation is to stare at this little
miracle and just let the oven keep running. Again, DO NOT LET IT RUN FOR
MORE THAN 2 OR 3 SECONDS!
Sometimes the steel wool will just glow red and not create a plasma.
In this case, open the door and remove the glass bakeware using oven mitts.
Dunk the glowing steel wool into water, and try again using a new sample of
steel wool. You may have to reposition the sample as far as height or
location is concerned because microwave ovens have "hotspots," where their
energy is concentrated. Do not let the microwave run for more than a few
seconds whether or not a plasma is created! Even without a plasma, empty
glassware can get very hot very quickly. The good news is that in my
experiments I get an ignition almost every time so you will probably not end
up having to futz with moving the equipment around to get it to work.
As a side note, you may wonder where to set the hot glassware down
after a successful demonstration. Because most people keep their microwave
ovens in the kitchen, one good spot is on a burner of the stove. Formica
countertops and wood and plastic cutting boards are not the best places to
set down hot glassware. In a pinch, you can use the top of the microwave
oven itself, as it is almost always metal, but this is no guarantee that the
heat will not char or damage the enamel! Don't blame me: I warned you! You
may end up having to break out the old "trivet," a metallic or ceramic
holder designed to support hot bakeware.
Where do we go from here? I believe we are at a point where the
materials and methods are now so refined that anyone can create ball
lightning on demand. We are past the trial-and-error stage. The use of
either carbon fiber veil (best) or steel wool (second best) avoids all the
inconsistent futzing that goes on with toothpicks and candles and pencil
leads and little metallic thingies.
I believe the next step is "doping" the plasma with metallic salts to
create various colors. My own experiments thus far have been hit and miss,
partly from an inability to easily obtain simple metallic salts. When I was
a kid, I would often read children's science experiment books that would
detail the wonders of creating colored fire in the fireplace by burning pine
cones soaked in various metallic salt solutions. Inevitably, the books would
say something to the effect of "just go down to the drugstore to buy your
supplies." Having been a pharmacist for about 15 years, I am here to tell
you PHARMACIES DO NOT CARRY METALLIC SALTS TO CREATE COLORED FIRE! Sadly, it
is becoming difficult to obtain even safe, simple metallic salts at all. I
am at a loss to give out an easy source for their supply.
I have been able to create an intensely yellow-colored plasma using
common table salt (sodium chloride) and a beautiful lavender with potassium
salts, but nothing repeatable enough for me to detail how someone else
should do it. I suspect green plasmas can be created with copper salts. I
look forward to seeing other people "take it to the next level."
<--- BACK TO BIGBALLS
Matt "The Tube" Crowley
October 6, 2004