Odds and ends

[Mark]

I charged up my electrophorus with my tiny negative ion device and 9 volt battery about the same size, instead of rubbing the dielectric vigorously with rabbit fur or something, and then made some sparks, this time in very dim light. So much more is revealed. I saw 4 or 5 sparks side by side arc over to my side. Then another variation was one or two arcs that then branch into a broad root-like structure hitting my body with a multitude of tiny branches. I wonder if in a vacuum an electrophorus would produce X-rays? I had a beautiful display tonight of a distance of well over three inches of sparkling fibers of light jumping from my electrophorus to my body, it was not the single spark you see in daylight, but rather a dazzle of multiple points launched at the same time and then branching into finer and finer divisions until becoming a bush of light. In the fall or wInter the static should be even better as you notice with your clothing or getting shocked by your car door and such that time of year. It's funny jam jars and electrostatic experiments both do better in dry air.
Sticky tape X-Ray
http://www.youtube.com/watch?v=r63e5y3Z3R8

“Some kind of microscopic lightning effect,” Dr. Putterman said. The scientists even demonstrated that the X-rays were bright enough to take an X-ray of a finger. That does not mean that tape dispensers on office desks are mini X-ray machines. The phenomenon has been observed only when tape is unpeeled in a vacuum. Something about air, moisture perhaps, short-circuits the X-rays."
http://www.nytimes.com/2008/10/28/science/28xray.html

[Mark]

Volta tidbit.
An additional invention pioneered by Volta, was the remotely operated pistol. He made use of a Leyden jar to send an electric current from Como to Milan (~50 km or ~30 miles), which in turn, set off the pistol. The current was sent along a wire that was insulated from the ground by wooden boards. This invention was a significant forerunner of the idea of the telegraph which also makes use of a current to communicate.[7]
http://en.wikipedia.org/wiki/Alessandro_Volta

[Mark]

If you scroll down, you can see some early prototypes of today's modern potato gun. ha
Also there are several curious creations you might like looking at, how long ago they were made, a different place and time. How simple the Volta pistol, and Volta's canisters resemble jam jar candidates.
http://www.sparkmuseum.com/STATIC_MISC.HTM

[Mark]

I'd like to have some of this plastic material to experiment with my electrophorus to see if I could make it more energetic. Anybody know anything about this plastic or if it's for sale somewhere? It's seems to create quite a good static charge as you can see.
http://www.youtube.com/watch?v=6mB-psw4Wxg

[Mark]

This caused me to chuckle a few times towards the end of the narration.
Jose s ROBIO 2006 presentation on gecko and biomimetics
http://www.youtube.com/watch?v=5_yFpOh7-Hg

[Mark]

Electrode tidbit.
"Substituting various types of sparking electrodes, such as balls of varied sizes, pointed electrodes, and wires will demonstrate that electrostatic discharges are influenced by electrode shape, and that the nature of an ESD strong influences the probability of ignition of flammable mixtures. For the lower voltage and higher capacitance of the piezoelectric sparker, wire electrodes seem more effective in producing good sparks for ignition. For the higher voltage and smaller capacitance of the electrophorus, smooth electrodes work better. This is so because higher voltages induce corona from sharp points which tends to dissipate any charge before an energetic spark can occur."
http://www.ece.rochester.edu/~jones/demos/ignition.html

[Mark]

Justick Electro Adhesion Notice Boards.wmv
http://www.youtube.com/watch?v=HjfqrzEcBjY

[Mark]

Just funny to see how much the petals look like pulsejet reeds.
Rotating Bennet's doubler
http://www.youtube.com/watch?v=UwqMINoFnpc

[Mark]

Electronic version of Bennet's doubler
http://www.youtube.com/watch?v=DikVuKpWNHM

"This device is being studied for application as electrostatic energy harvester. A version can be possibly built by MEMS (microelectromechanical) techniques in an integrated circuit and used to harvest energy from ambient vibration."
"In October 2010 I completed a new version of the same device, designed to have enough capacitance between the plates to be unstable even when completely discharged. The machine was built as a rotating machine, with two rotating central plates moving between two fixed groups of three plates. The plates were made of acrylic, covered by aluminum tape. The fixed plates are connected to terminals below, and the rotating plates to the insulated central axle, that has a terminal in contact with one of the ball bearings that support it. A small motor turns the machine. The diodes are as in the previous version."
"Measurements on the machine will be made soon. The machine worked as expected, never failing to start without previous excitation. The five diodes in series used don't appear to be a problem for the self-excitation. It reaches about 6 kV, limited by the maximum reverse voltage of the diodes and by internal sparking."
http://www.coe.ufrj.br/~acmq/bennetd.html

[Mike Everman]

That was a good one.

[Viv]

My first thought on seeing that was "Wimshurst machine" but then I noticed the crank and thought WTF a reciprocating Wimshurst machine

Very interesting find that, I enjoyed looking it up and realizing it was capacitive commutation, here are a few links for those interested in further reading

Bennet's doubler
http://www.coe.ufrj.br/~acmq/bennet.html


Wimshurst machine
http://www.coe.ufrj.br/~acmq/electrostatic.html

Viv

[Mark]

A thought crossed my mind the other day when I was playing with my arduously heavy aluminum disc/old turntable and acrylic with foil electrophorus. Since I have some 16 inch aluminum plates scheduled to arrive tommorow, I thought it might be fun to do the same as the back and forth motion, but even before I saw that topic, it occurred to me that maybe I could leave one disk on the table and have the other of the same size on a shaft fall to the one below. Then have a spring or something to break the fall, maybe getting a little bit of pogo-like action like my sleeved quartz tubing device and I could help it along by adding a push every now and then or put some neo magnets in a repelling position to break the fall and provide some sort of oscillating motion, maybe use the pneumatic spring effect of my Bimba cylinders even, I don't know. It looks good on paper but might be hard to build.
My electrophorus really puts out a good 2 inch spark when I briefly energize/charge it with my tiny negative ion device. Then I can remove the ion device and lift the turntable disc straight up as many times as I like and get a good spark. If you lift it fast it produces the best spark, and sometimes it will arc to the acrylic before I can get a chance to spark it over to my body.
This Kamachi device might be kind of like the copper plates in a way.
http://www.ece.rochester.edu/~jones/demos/kamachi.html

"A "shake-sphere" machine [10], built by Joachim Bolz and his students in 1997. It is an influence machine using two balls in a tube, moved by shaking the tube, instead of disks. It works as my Toepler machine above. An schematic diagram of it. Photo and drawing by J. Bolz. Operation of the machine."
http://www.coe.ufrj.br/~acmq/shaking.jpg
http://www.coe.ufrj.br/~acmq/shakings.gif
http://www.coe.ufrj.br/~acmq/shakesphere.gif
Forgive me/a bit silly, but this concept came to mind too, have some springs for the above two balls in a tube/shake-sphere machine.
http://www.youtube.com/watch?v=dD0GjMlJsD4

[Mark]

Static tidbits.
"Actually, no friction or rug-scuffing is required in order to electrically charge your body. The need for friction is a widespread misconception. While it's true that the friction will increase the charge-separation process, friction isn't the cause. Whenever two different insulating surfaces touch together, opposite charges found within the two surfaces become separated. Simply walking across certain rugs or plastic flooring will cause your shoe soles to touch the dissimilar material of the rug. This is enough to separate the negatives from the positives and create imbalanced electric charges on the bottoms of your shoes."
"NOTE2: In private communications M. Foster mentioned that if you blast a hair dryer through a PVC pipe after first wetting the inner surface of the pipe, the pipe becomes highly electrified. The cause is unknown, but it might involve the bursting of microbubbles (which are known to launch negative water droplets into the air.)"
http://www.eskimo.com/~billb/emotor/zapped.html

[Mark]

I was thinking about building this one too, something that doesn't require too much skill, my type of project.
"The Lorente generator. A triboelectric machine composed of four cylinders that roll together without friction, under a slight pressure. The two outermost cylinders are metallic, and the two central cylinders are of distinct insulating materials (nylon and teflon). Opposite charges are collected in the metallic cylinders. The basic machine produces voltages of some tens of kV, but several modules can be stacked for more voltage. A coaxial version is also possible. Pictures from actual models are here and here. This device was invented and patented by G. Lorente, who sent the pictures."
A,B,C,D
http://www.coe.ufrj.br/~acmq/lorente1.jpg

"It consists (see figure) of four equal cylinders or rollers, with their axes parallel to each other and always in contact with the colateral ones by mean of springs. All the axes are in the same plane . Rollers are able to rotate in steady mutual contact without sliding. The two external rollers are metallic and the two inner ones are made of suitable dissimilar dielectric materials. For my models I selected teflon and nylon respectively."
"Very suitable for electrostatic experiments and demos at laboratory. Prototypes made and tested provide voltages in the range of 30-50 KV with currents in the range of microampere, enough for many classical experiments. Larger voltages could be obtained with larger sizes and/or stacking many units."
"US Patent is for sale. Price US$ 1,100,000" (Maybe a bit optimisitic but apparently a simple static idea can be worthy)
http://info.uned.es/electrostatic-generator/index.html

Some other static links ...
http://www.electrical-contractor.net/ES ... 20Page.htm

[Mark]

Just another thought/tidbit for inspiration maybe.
"New and stirring things are belittled because if they are not belittled, the humiliating question arises, 'Why then are you not taking part in them?' " - H. G. Wells
http://www.eskimo.com/~billb/emotor/mestat.html