This is just something I threw together that I thought you might find useful. comments?
... perhaps I should categorize these into "pulsed power" (including coilguns, strobe guns) vs. "continuous power" (including Jacob's ladder).
FIXME: move this stuff to http://www.communitywiki.org/odd/MadScientist/HighVoltage /* was http://oddwiki.taoriver.net/wiki.pl/MadScientist/HighVoltage */
"Who hath divided a watercourse for the overflowing of waters, or a way for the lightning of thunder ?" -- Job 38:25
http://home.navisoft.com/rossengineering/ Dangerously high voltage stuff.
Micro Linear Corp http://microlinear.com/ sells $2.25 (in 1 000 s) ML4877 designed to power cold-cathode fluorescent lamps for backlighting LCDs. "up to 2 KV ... up to 30 W"
there's a clever high-voltage static electricity generator at http://www.amasci.com/emotor/kelvin.html which also has other pointers to high-voltage electrostatic projects, and more construction tips: wood is surprisingly conductive at these high voltages; fishing line makes a good insulator, etc. /* was http://pw2.netcom.com/~tonyh3/ */
Geoff has also build this device, and put some nice photos online: http://www.angelfire.com/ak/egel/kelv1.html
Here's a local copy:
"Kelvin's Thunderstorm" or Lord Kelvin's water-drop electrostatic generator Bill Beaty, 1995 It is possible to build a very simple high voltage generator which has no moving parts and is powered by the energy of falling water. By dribbling water through some old soup cans, several thousand volts magically appears. The magic lies in the fact that water (as well as everything else!) is made of vast quantities of positive and negative electric charge in perfect cancellation. This device is a gravity-powered charge un-canceller. The basic idea is this: |||||| |||||| Grounded |||||| Water |||||| Dripper |||||| |||||| \ / - || - - _ - _ + + + + + + + -o- + -------------- + - + | | + + | positively | + _ + | electrified | + -o- + | object | + - + | | + + | | + Negatively + -------------- + electrified _ + + + + + + + droplets -o- - Fig 1. CHARGING OF WATER DROPLETS BY INDUCTION Water is full of movable charges, half positive, half negative. The positive object causes separation of charges in the nearby water by drawing an excess of negative ions into the tip of the water dripper, while repelling an equal amount of positive ions back into ground. When the water drop detaches from the tip of the dripper, it carries away negative charge, leaving the earth slightly positive. This is interesting in that the positive object never needs to lose its charge imbalance, yet the negatively electrified water drops will be created continuously forever, as long as the water keeps flowing. The electrical energy is all created by the work that gravity does in pulling the negative droplet away from the grounded dripper and away against the attraction of the positive object. (Note: the charge polarities can be reversed: if the "object" is negative, the droplets would be positive.) Suppose you build two of the drippers in Fig. 1, set them side by side, then collect the electrified water drops from one side and use them to electrify the "charged object" on the other. You'll then have a self-sustaining electrical reaction. The negative droplets touching the lower can of one assembly will charge the negative upper ring of the other, and the positive droplets on the other side will touch the lower can and charge the upper ring of the first side positively. The grounded drippers are connected to each other and to ground. This all is illustrated in Fig. 2. In fact, if you build such a device, it will usually create voltage spontaneously without being pre-charged. Kelvin's complete generator device looks like this: __________________________ _ _____________________ \ \ \ \ \ \ \ \ \ \ \ \ \ || || || || || || || || || || grounded drippers (need not be metal) || || == == == == metal disks with holes, or wire rings, or bottomless metal coffee cans, or bundt pans (supported by insulating rods) | | | | | | | | | | | | metal cans on insulators (styrofoam?) | | | | |____| |____| | | | | | | | | |__| |__| Fig. 2 TWO DROPLET-CHARGERS PLACED NEAR EACH OTHER (no wires shown) Wires are used to cross-connect the cans and the wire rings. The two diagonal wires must not touch together: __________________________ _ _____________________ \ \ \ \ \ \ \ \ \ \ \ \ \ || || || || || || || || o + + - - o + == ==----\ /---== == - o + \ + - / - o + \ / o C/ o - | | - / \ + | | + - | o | - - / + \ + | o | + | |_____/ \_____| | - |----| - + |----| + |____| |____| | | | | | | | | |__| |__| Fig. 3 KELVIN'S THUNDERSTORM, W/WIRES SHOWN OPERATION Once you have the water dripping, you can expect high voltage to immediately appear. Touch one of the coffee cans gently and listen for tiny "static" sparks. Obtain a small "NE-2" neon pilot light, hold it by one wire, then touch one of the cans with the other wire. You should see a dim orange flash. Touch a can on one side, then a can on the other, and you should receive a tiny spark each time. Don't connect the NE-2 directly across the two wires or it will short out the generator and prevent high voltage buildup. Instead, you can connect the NE-2 to one of the generator's wires and bend it so the NE-2's other lead is very close to the other wire. Small sparks will jump across the small gap and flash the NE-2. The smaller the gap, the faster yet dimmer the flashing. HINTS If none of this works, it may be because the humidity is high and your device is having trouble "deciding" which side should be positive and which negative. It takes voltage to make voltage, and if your device starts totally at zero, it may take a minute or two to build up to maximum. Try holding an electrified object briefly near the cans (for example: a balloon, a 2liter pop bottle, or some styrofoam, each rubbed on hair to electrify.) The energy that builds up between the cans comes from the falling of the water, and as the stored energy grows, the water has to do more and more work to add a bit more charge imbalance to the cans. The electrified drops feel a repulsion force as they fall towards the like-charged cans, and as the voltage increases, the drops will fall more and more slowly. They may even start bending their paths, even occasionally falling upwards! If the device is run for very long, the lower cans fill up. How to get the water out of the cans without discharging them? Here's my addition to the classic Kelvin Waterdropper: use the "faraday ice pail" effect, where a conductive hollow object always has no charge inside. Connect an exit tube inside each lower can as below, so the water DRIPS out (if it falls in a solid stream, the cans will discharge.) || || || || || || || || ||/\/\/\/\/\/\/\/\/|| || || For best results, no sharp edges or || || burrs anywhere. || WATER || || || || __ __ || || | | | | || || | | | | || || | U | || || | O | || ====== ====== O Uncharged drops O exit from bottom Fig. 4 REMOVING THE WATER FROM THE LOWER CANS Or, even simpler, install a cone-shaped piece of metal window screen inside a bottomless can, so the water drops touch the screen and continue through. Make sure the screen is vertically centered, so that the point of the cone doesn't extend past the lip of the can. With a little catcher-tray and a fountain pump, you can make the system recirculate. Or, you can stack all four parts of one Kelvin device in a single row, for an in-line waterdropper generator. \ \ \ \ \ \ || || || || o o | | Neg | | can | o | | | Pos | | can |...| w/screen | | | | \ / Connect pos to pos, neg to neg Grounded \ / Funnel || o | | Pos | | can | o | | | Neg | | can |...| w/screen | | | | o Fig. 5 IN-LINE VERSION (wires not shown) The water supply need not be a "dripper", it can be a high velocity spray, as long as the jet divides into droplets, not a contiguous stream. And multiple jets can be used, sort of like a shower head. I've always wanted to build a gigantic version that works like that below, with hollow metal toroids. (Use halves of VandeGraff spheres, the halves with the holes): \\ \\ \\ \\ \\ \\ || || || || water || || spray || || ___ ___ ___ ___ / \ / \ / \ / \ | | | | | | | | Four torii \___/ \___/ \___/ \___/ (shown cross- sectional) ___ ___ ___ ___ / \ / \ / \ / \ | |\ /| | | |\ /| | \___/ \_/ \___/ \___/ \_/ \___/ conical screens in lower torii touch droplets and release, discharging them. Entire screen assy must be deep within the "hole" of each donut so the torus shields it from the field on the outside. Fig. 6 GIANT KELVIN DEVICE BUILT FROM SPUN-METAL DONUTS High-velocity waterjets and hollow-pipe cross-connecting conductors complete the scene: a "VandeGraaff Generator" version of Kelvin's Thunderstorm apparatus! The above generators can be used to run a motor, if the motor is my Pop Bottle Electrostatic Motor at: http://www.eskimo.com/~billb/emotor/emotor.html I find that the Kelvin Waterdrop Generator is a little too feeble to keep the motor going continuously. Instead it builds up a charge imbalance, then the motor starts turning and rotates a few times, the imbalance is exhausted, then it builds up again and repeats. This happens a couple of times per minute. Perhaps if several generators were connected in parallel, the motor would run continuously.
Subject: Re: Homebuilt EDM ? From: email@example.com (WAnliker) Date: 1998/06/06 Message-ID: <1998060614102200.KAA00941@ladder03.news.aol.com> Newsgroups: rec.crafts.metalworking [More Headers] [Subscribe to rec.crafts.metalworking] Home Shop Machinist published a construction series on the EDM. It is available in book form from: The Home Shop Machinist PO Box 629 Traverse City , Mich. 49685 1-800-447-7367 Bool is titled: BUILD AN EDM 56 page, softbound 8.5 x 11 @$17.00 This is a complete construction manual, mechanics, electronics,
Railguns and coilguns have many characteristics in common (nearly constant acceleration down the barrel, exit speeds not limited by the speed of sound, accelerates only the payload -- not the engine/energy source, etc.).
"If people stop to watch, you're doing something right"
"Saving Mir with a rope trick" http://teaser.ieee.org/pubs/spectrum/0700/mir.html article by James Oberg in _IEEE Spectrum_ 2000-07
Perhaps you could design something to overcome these disadvantages ? [FIXME:...]
Q. Where can I get a device that detoxifies bites or stings?
A. A hand-crank high voltage device, using no battery, has been developed for base use, such as in a clinic. This hand-crank detoxifier unit operates by cranking a handle that produces high voltage sparks. Its primary advantage is that you can adjust the amount of "zap" by the speed at which you crank. The disadvantage is its weight (about 8 lbs.). This unit is subsidized by donor gifts and is free to SIL translation and literacy teams. Other SIL members can purchase this detoxifier from JAARS at a cost of $100. JAARS can furnish these units to SIL members only (part #HCSNB). Order by email: firstname.lastname@example.org. Non-SIL individuals may purchase directly from the manufacturer, Wade Teague, 3321 Vaucluse Road, Aiken, SC 29801, phone (803) 648-1396. NOTE: We do not suggest that anyone use this treatment in lieu of accepted medical procedures for the treatment of venomous animal bites. The procedure is in the research stage. Always seek proper medical attention and render appropriate first aid to victims.
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