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Creative science & research make your own high voltage capacitors


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  • 1. Make Your Own # HVC1 Copyright 1996 - 2003 High VoltageCAPACITORS Creative Science & Research PO BOX 557 New Albany, IN. 47151 USA
  • 2. Make Your Own #HVC1 Copyright 1996 - 2003 HIGH VOLTAGECAPACITORS 10,000 to 25,000 volt capacitor 10,000 to 25,000 volt capacitorIn our above HV Capacitor design, we used a clear plastic make up container that wepurchased from a local K-Mart Store in the women’s dept. We then purchased 5” x 50 footaluminum sheeting from a hardware store, you will need 2 rolls. We then cut the aluminumin small pieces of 5” x 6” sheets. Once you are done with cutting both rolls up. Then you willneed to make your bolt holes on the ends of your positive and your negative plates. You willneed a good 3-M spray adhesive, which must spray a fine spray, you canpurchase this at any Hardware or Art Store. Now you will needto cut 6” x 6” plastic Mylar pieces for your die electric. You willneed to bond them to the aluminum plates. Use a 3 milor a 4 mill plastic, this should hold up under 10,000 vdc. +Cut a small piece of ½”plywood to 5” x 6” then drill your boltholes using the + and negative plate as a template, Now youwill need a small drill press, set up a wood jig with registermarks so you can drill holes in all the other aluminum plates _in the exact same spot. Holes should be a little bigger thanthe bolt. Even out 2 stacks of 5” x 6” aluminum plates, start offdrilling the one stake first and mark each one as +. This will helpyou later and you will thank me for it. Then do the Neg plates the same way. Make sure youdrill holes in the exact same place, so all bolt holes will line up correctly when you push theholding bolts through. When you are finished drilling holes, place 4 guide bolts through thebottom of your plywood base. Using these bolts as guides. Now spray the top of theplywood with adhesive. Now place your first 5” x 6” + plate on it, press down firmly. Nowspray your mylar plastic on a sheet of cardboard away from your project, spraying only oneside, you want to keep the spray away from your project or it will build up on your bolts. Nowplace the mylar to the right side of the holes, press firmly, now spray one side of your Neg.Plate and insert over the right side bolts. The left bolts are for your + plates and the Rightside is for your Negative plates. Now repeat this over and over again. Be careful and not to forget toplace Mylar plastic in-between each + and Negative plate. Or they will short out.It will take you about 16 hrs of work to finish, once you are done place 2 bolts on the top of your plastic lid.Connect the left one to the left bolts using 8 guage wire or wire rated for the amount of voltage and amperageyou are going to use capacitor for, do the same for the right.
  • 3. Free News / High Voltage capacitors MAKE YOUR OWN HIGH - VOLTAGE CAPACITORSAs one who supplies parts to those It is feasible to build your own ca- dielectric. A dielectric may be solid,who experiment with high voltage, pacitors of any voltage and energy gel, liquid, or gas. A capacitors abilityI get a lot of letters from frustrated storage size for either AC or DC use. to store energy is measured in eitherbuilders Who can not find a High The process involves a step-by-step microfarads ( uf ), nanofarads (nF) orVoltage Capacitor at a low price. logical approach that well present picofarads (pF). Micro means one milan inexpensive XXX microfarad ca- here. Well explain how to plan and lionth, nano stands for one billionthpacitor at a working voltage of YYY? construct a capacitor, where to get and pico for one trillionth (farads areMy only source wants $249 for one." materials, safety considerations, tips also used, but in high voltage workSometimes, a high price is justified; and hints, and include a few simple they are impractically large units).other times, a seller has the only ca- projects, Several factors affect capacitance.pacitors of a special value available, The formula for determining capaci- A Capacitors Description. A ca-and will soak you for the maximum tance is; pacitor consists of two or more platesdollar. of a conductive material separated C=(0.224KA/d)(n-1) It is feasible to build your own ca- by an insulating substance called a Page 1
  • 4. where C is the capacitance in dielectric. It also has the advantage picofarads. K is a constant that de- WARNING! This free artical of of being easy to glue to with Silicone pends on the insulator (or dielectric) RTV or Krazy Glue, and it is readilybetween the plates (called the di- news deals with subject matter available and cheap. However, it iselectric constant), A is the area of one that can be hazerdous to your fragile, and may contain impuritiesconductive plate in square inches, d is health and life! Do not try to that allow conductive paths for de-the separation between adjacent build these devices unless you structive arcs. Contradictorily, for yourplates in inches, and n is the number are skilled in the art of high first capacitor or two, we suggest thatof plates. As you may know, different voltage. You build at your own you try a type made with glass to gaininsulators have different dielectric risk, we are not responsible for experience, since they go togetherconstants. Table 1 shows the values of anythingin these plans. Use easily and are cr)eap.K for some common materials and rubber gloves and rubberv Many industrial capacitors are oilthe peak voltage they can withstand shoes when working with high filled. Oil has an extremely high resis-per 1/1000th inch (called a mil) of thick- voltage. Discharge all tance. so It does not measurably in-ness. This rating is called the puncture capacitors before touching crease leakage. Silicone transformeror breakdown voltage. oil is the best liquid insulator, but is Dielectrics. The better the insulat- rather hard to obtain. Mineral oil. on ing property of the dielectric, the with high quality steel drill bits or spe- the other hand, is readily available higher its resistance, and the less di- cial plastic bitsJhey must be drilled at from most pharmacies. Although itelectric leakage loss present. In low has a low dielectric constant, it can 300 RPM or slower to prevent chip-current, high voltage power supplies, be used in a variety of simple ways to ping and melting, and be sure tominimizing all sources of loss is impor- make very good high voltage capac-tant to prevent undue power-supply leave the protective film or paper on itors.loading. For that reason, plastics are the plastic when working with it. For example, a dandy variable DCby far the best materials for large ca- Mylar, Polyethylene, Nylon, and es- capacitor can be made by immers-pacitors. A serious project should in- pecially Teflon are difficult to work with ing a junked AM-radio tuning capaci-volve one of the plastics. as they are very slippery. The best way tor of the movable-plate type in Lexan. Polystyrene, and Plexiglas in to attach plates to any of those mate- mineral oil so its shaft and connectionparticular are easy to glue, and can rials is to use a glue specifically de- leads come out of the containers cut with a table saw using a plas- If you wish to try this idea, make abso- signed for the material. Polyvinyltics blade, or a carborundum impreg- lutely certain the "cold" plates of thenated all-purpose cutting blade like chloride (or just PVC) is moderately slippery It can be glued with a PVC capacitor (the moving plates) are atZippity-Do (which is cheaper). A sabre ground potential. Use a good, large,saw with a really coarse wood blade cement, or foil plates can be at- non-metal knob for adjustment. A 100-will also work (other blade types clog tached using silicone RTv to 365-pF variable capacitor with a 1-or chip). Such plastics may be drilled Glass is, in principle, an even better kVDC breakdown voltage (/.e./ a plate spacing of 1 mm) becomes a 270- to 985-pF unit with 7500-VDC break- Dielectric Puncture Voltage Insulator Constant per 0.001 Inch Notes down rating. Try pricing a 7500-volt variable capacitor sometime, and Air 1.0 30 1 youll see the advantage to this ap- Window glass 7.8 200 proach! Polyethylene 2.3 450 You can use mineral oil in designs of Paper(bond) 3.0 200 your own. too. Immersion of a home- Polycarbonate (Lexan) 2.96 400 Teflon 2.1 1000 made capacitor in mineral oil will Polystyrene 2.6 500 greatly improve its voltage rating and lifetime. Epoxy circuit board 5.2 700 2, 3 Pyrex 4.8 335 Paper is an excellent dielectric Plexiglas 2.8 450 when saturated with mineral oil. Try PVC (rigid type) 2.95 725 20-lb. bond computer paper which Silicone RTV 3.6 550 has a 4 mil thickness. Prepare this inex- Polyethylene terphthalate (Mylar) 3.0 7500 pensive capacitor by interleaving Nylon 3.2 407 4 4 layers of dry paper with aluminum foil, Mineral Oil. Squibb 2.7 200 2, 5 and then immerse the capacitor in oil Shellac 3.3 200 until the paper gets saturated. One disadvantage to using oil in NOTES: All measurements at 1 MHz unless otherwise noted. 1 Tested with dry air, home-made capacitors is that the 2 Tested at 300 HZ using a Healthkit IM-2320 Multimeter and homemade capacitor. tape or glue used to bond the assem- 3 Estimate, based no experiences. bly must be oil-resistant. Silicone RTV is 4 lowest value of 3 types. the best glue for these purposes. 5 estimate. Probably higher. A 0.040" gap withstood over 10,000 volts DC before break Down in one test. Design Considerations. There are Page 2
  • 5. High Voltage Safety High voltage is considered any value over 500 v AC or DC. When you attach a capacitor to high voltage, you are multiply- ing its hazard many fold! Therefore, experi- menters must take extra precautions to avopid painful shocks and possible elec- trocution. Here are a few guidelines to fol- low when working with high voltage: Label your project in several locations with: “ Danger High Voltage” where appro- priate. Such a warning label is provided here for you to copy. ( See Fig w ). Keep Children, pets and others away from your capacitor etc... Cover all bare leads, wires, wires, connection terminals, and possible points of contact with high voltage putty or a cover painted on with rubber paint or clear plastic. Work in a dry location. Working in a damp basement may cause problems. Wear rubber soled boots or sneakers. Stand on a thick rubber mat. Fig. W. Copy this WARNING label and tape it or past it on or around your projects. Never put your body in a position to become a conductor, Locate your HV project away from appliances, metal doors designs first to get used to techniques window frames, heating ducts, vents,several things to consider when de- radiators, metal sinks or water pipes. Allsigning and constructing your own and quirks before you invest lots of these items can become a deadly ground ifcapacitor. Lets point out each one time and money your body comes between them and highbefore moving to the construction de- You must also take into considera- voltage.tails. The first and most important thing tion the voltage that will be applied to Always pull the plug when working on ato concern yourself with is safety De- the capacitor. That will affect your high voltage circuit unless you when youspite the romance of high voltage, it is choice of a dielectric and thus its re- must test it. Use caution. Keep one handfoolish to needlessly risk your life. Since quired thickness. Should you use an in your pocket. Use a high voltage probyou will probably be working with le- whenever possible. Use NE-2 neon lamps inadequate dielectric or thickness. to indicate live or stored high voltage. Bledthal voltages, observance of all safety sparks or arcs can result. A spark is a off the charge on capacitors with a powerpractices for high voltage (or HV) is temporary breakdown that a lot of resistor before performing adjustmentsabsolutely essential. For some capacitors will survive, but an arc is etc...Use good ventilation, projects usingguidelines, see the boxed text entitled Tesla coils and Jacob’s ladders give off serious: it is a path burned into the Ozone."High Voltage Safety" dielectric or other component. Arcs The next aspect to consider is ca- carbonize materials, producing apacity If you have a specific capaci- highly conductive channel that oftentance in mind. you can design a renders an apparatus useless andcapacitor using the information pro- very likely dangerous. Except in spe-vided elsewhere in this article. Try one cial cases where the insulator is aof the designs described later. Or per- "self-healing" type (like air. oil, and that often appear in materials thathaps you prefer experimenting in- some plastics), a single arc will ruin the are not highly refined for capacitorstead. Either way, when building forthe first time, we suggest making small capacitor. use, we must add a safety margin to To compensate for the impurities the thickness of the dielectric. In the Page 3
  • 6. case of DC, a good rule of thumb is a50 margin, For example, say you 2” x 6” Aluminum - Foil Tab Secured with Crazy Glue. Copper-Clad PC Boardneed a 500-volt DC capacitor usingpolystyrene, Consulting Table 1, notepolystyrenes breakdown is 500 volts 1” Edge Marginper mil, thus 1 mil is required. Adding50 gives you 1.5 mils, which is ade-quate for pure DC, You can always usea thicker dielectric if its expedient,providing that you adjust the numberof plates or their size to accommo-date the wider plate separation. Itshould be mentioned that when mak-ing a paper capacitor, you should usea healthy safety margin since paper isnot always uniform in thickness. In comparison to AC, DC puts rela- 12” 10”tively little stress on a capacitor. Bycontrast, AC reverses the dielectricspolarity every cycle. So the dielectricin an AC capacitor must have twicethe thickness required in an equiv-alent DC capacitor. Further, whenconsidering dielec+rics in AC applica-tions. you must deal with the peak volt-age—not rms (/?oot Mean Square)voltage—that they will be exposed to,If you wish to convert an rms voltageto its equivalent peak sinewave value, 12”multiply it by 1,414, So, to roughly calculate the proper Fig. 2. For a single-section capacitor, use one double-sided PC board. For multiplevoltage rating needed for an AC ca- sections, use several single-sided boards damped together or bolted together with nylon screwspacitor, you first double its requiredrms voltage rating then multiply by dielectric material to use since it has a breaks down gradually upon ex-1.414. To further simplify this calcula- very high puncture voltage per mil, posure to ozone gas (always presenttion, all one needs to do is multiply the and thus makes a very compact ca- around high voltage) becoming brit-AC (rms) voltage in question by 2,828. pacitor. Plastics are light, so most ca- tle and less resistant to arc puncture.Now divide the voltage by the punc- pacitors will weigh less than ten That brings us to another importantture-voltage rating to get a prelimin- pounds, The toughest plastic is Lexan, consideration: the capacitors usefulary thickness value. Finally, you must which is difficult to crack even with a life. To enhance a capacitors lifeadd a safety margin of 50 to 100. hammer and is often used for vandal- keep the working voltage at or belowThe actual percentage depends on proof windows, Glass is the worst ma- the rated specification in both DCthe characteristics of the applied AC terial for a lightweight, durable ca- and AC applications. We discoveredvoltage. For a pure sinewave AC, we pacitor, and can even crack under its that charging at no more than 70 ofsuggest a 50 safety margin whereas own weight when lifted. Take all this a capacitors working voltage resultedhigh frequency, non-sinusoidal ap- into account when selecting your ma- in an amazing 10-fold increase in life-plications such as Tesia coils require a terials, time for one type of commercial ca-full 100 extra thickness. Of course, the overall cost in labor pacitor. Also, for DC capacitors, watch If one is available, equip an os- and materials should also be consid- out for voltage reversals, If your systemcilloscope with a high voltage probe ered before constructing a capacitor. has a lot of inductance, reverse volt-to visually observe exactly what the Calculate beforehand the cost of age swings are always produced. In-circuit is doing so you can determine your materials. Paper and poly- crease the safety margin if a lot ofthe proper safety margin. An os- ethylene are the cheapest. Glass is inductance is in the circuit. Further-cilloscope will also enable you to de- the next higher price. Labor time is more, the temperature should betect destructive voltage spikes and about the same with Plexiglas, Lexan, kept below 120°F As mentioned ear-superimposed AC (also called AC rip- and glass sheet capacitors, Exotic lier, watch out for superimposed AC, ple) so you can design a capacitor to plastics such as Teflon are not needed voltage spikes, and ringing. These handle those harmful excursions. unless your application demands ex- types of AC waves can drastically Of course physical size, weight, and treme chemical and thermal deterio- shorten lifetime, Tesia coils have noto-fragility are also important charac-teristics of capacitor design. If you ration resistance. Polyethelene has rious ringing. To repeat: if feasible, use have size limitations, Mylar is the best excellent chemical resistance, but an oscilloscope to visually analyze Page 4
  • 7. your circuit. Often a power resistor in- tor plate, or anywhere the shape of a Whether a capacitor is enclosed orserted in the current path to the ca- conductor changes abruptly (such as exposed, discharge paths must bepacitor quenches ringing, With this the tip of a nail) is called point dis- wide enough to avoid arcs to thecriteria under our belts, lets look at charge. It can be readily observed in case. adjacent plates, terminals, con-some problems your design and con- a dark room at very high voltages. nections, or components, That is es-struction methods should prevent. Small, bright blue pinpoint(s) are seen pecially important in situations where leaking electrons into the air, accom- conductors must be left uninsulated,Signs of Trouble. Your assembly panied by a hissing sound and copi-techniques should seek to minimize Note that the space from each plate ous ozone production,the likelihood of a few possible prob- to the edge of the dielectric must be Once again, insulation and properlems, Luckily, all of them can be pre- wide enough to stop any spark from ventilation are the proper solutions tovented at least in part by using ample "crawling" over the edge of one plate all these problems, and there areamounts of insulating material such as to another. some specialized techniques to insu-No-arc or Corona Dope and/or high Power leads must be capable of late your capacitors and otherwisevoltage putty on all exposed areas, A withstanding the full voltage of the improve the safety of your high volt-plastic case to enclose the apparatus charge plus at least a 50 safety age projects, Lets get to those also recommended (more on that margin. TV anode wire, which comeslater), Construction Requirements. A key rated up to 40-kVDC, makes great Still and all, you should know what ingredient in a good assembly is a leads, Vinyl tubing or aquarium airproblems the insulation is preventing. proper case. Your capacitors housing hose may be slipped over leads toThe first problem insulation relieves is must protect it against moisture, dirt, increase their voltage rating,the possibility of electrical shock, and accidental discharge. Plastic Make sure the plates are securely Insulation also minimizes the pro- cases for dry capacitors are easy to mounted or they will tend to shift, or duction of ozone—a gas created make with acrylic sheets glued at all make a noisy rattle when used withwhen high voltage causes three oxy- corners with Silicone RTV Oil-proof AC. Glue or compress the assembly to gen atoms to join together. Ozone has cases can be made for immersed hold it secure. With regard to mount- a tart, sweet "electrical" smell, and is models, but you will need to rough-up ing, keep in mind that glues that dry 100 times as poisonous as carbon the plastic at the sealing edges with by evaporation of a volatile chemical monoxide, Beware: it quickly causes sandpaper and use both a bonding might not set properly if "buried" in- headache, nausea, vomiting, and re- and second fillet glue coating for a side an assembly away from air, and spiritory irritation, In addition to insulat- liquid-proof seal, Metal cases can be could thus become a fire hazard. ing all the exposed HV areas, you made from PC boards cut on a shear Rolled-up capacitors may be held should also operate your equipment or large paper cutter and soldered at securely by wrapping the interleaving with good ventilation if it produces the edges, Copper roof flashing layers of foil and insulator tight around any ozone, (available at hardware stores) works an insulating mandrel and then tap- Closely linked to ozone generation well too. However when using metal, ing with a clear PVC tape, Where nec- is corona leakage, It is produced by a always beware of contamination by essary coat the ends with Silicone RTV charge being leeched off a highly solder rosin, solder bits, and other That will eliminate end-arcing flash- charged object by the air, That typ- crud, which can short out plates or over and corona loss. Alternatively al- ically produces ozone. However, otherwise reduce efficiency though it is somewhat brittle, paraffin sometimes a device (such as a Van (with a puncture voltage of 250 volts/ deGraff generator) is constructed specifically to display corona dis- charge, and insulating it would defeat that purpose, In such cases, good ventilation is the only practical means of hazard prevention. Ozone can also be created by arc- ing, which can occur anywhere, How- ever, ozone production is not the greatest hazard arcing presents, At 50 kV a spark can arc between an unin- sulated contact and your body if you come within 2 inches of the contact, Arcing commonly takes two forms: di- rectly through a capacitors dielectric (as mentioned earlier), or across the edges of a capacitors plates to an adjacent plate, A snapping sound in- dicates the presence of arcing, so Fig. 3. With this design, you may stack as many plates as you wish, provided there are keep your ears open, an equal number of plates attached to each lead. Arcing from the edges of a capaci- Page 5
  • 8. with an insulating dielectric between them. By now, we hope you have a good understanding of the principles and techniques involved in making your own capacitors. Without forgetting safety, lets talk about how to build some simple capacitors/any of which can be modified for your application. A Leyden Jar Capacitor. Leyden Jars are one of the first types of ca- pacitors made, having been inven- ted nearly two and a half centuries ago. Their development was first re- corded in 1745 by Ewald von Kliest, In 1746, Peter van Musschenbroeck of Leyden, Holland experimented fur- ther with the invention. We can build our own modernized units with a gal- lon-size wide-mouthed mayonnaise jar. The project only costs about $2, and is good to at least 10 kVDC at 2,5 nR Units weve tested at 15 kVDC did not fail; at that voltage, the capacitors stored just under Vs joule each, First select a jar without bubbles, cracks, or blemishes and that has a mouth large enough to comfortably slip your hand through. Next, carefully clean it out. Youll use aluminum foil inside and out as the conductive plates (see Fig, 1), Cut a foil disk 1-inch bigger than the bottom of the jar. Now coat the dull side of the foil and inside jar bottom with a thin, even layer of rubber cement, Let both dry for 10 minutes, and press together. fig. 4. A rolled-up capacitor, like that shown here, can provide the greatest Smooth with firm hand pressure, Avoid capacitance in the smallest space. Note that tl-ie dimensions in the side view have been excess wrinkles. Do the rest of the in- greatly exaggerated/or the sake of clarity side except the top inch of the bottle using three or four pieces of foil, (It is easiest to do the plate in pieces in-mil) is an excellent insulator for the balls make good terminals, Clean stead of all at once. since rubber ce-ends of colled-up capacitors and the them up with a wire brush or steel ment "grabs" and it is difficult to re-edges of flat-plate type capacitors, If wool to eliminate rough spots, The au- position the foil once contact hasyou want to use melted paraffin wax, thor uses fishing floats covered with been made.) Now do the outside foilheat the wax only in a double-boiler either aluminum foil or nickel print plate in pieces, leaving the top inchpan. since if it gets too hot it can catch paint for up to 10 kVDC, Split the bob- bare, Check the foils with a continuityfire. Be sure to apply several coats, bin first with a rator blade, remove the tester to determine if the pieces are inallowing the wax to harden between line holder and spring, and glue it to- good electrical contact. Areas of foileach coat. Liquid electrical tape also gether again with epoxy. not in contact can be bridged withmokes a great end seal, however it is Furthermore, as you work, keep all strips of foil or nickel-print paint.somewhat hard to find. Try mail-order materials as clean as possible. Not For the top cover, cut two disks ofdistributors for that product, only will your work have a better ap- clear plastic, one slightly smaller than High voltage terminals for your proj- pearonce, but arcs and burn- the rim, the other ^-inch larger thanects can be made from plastic rods throughs due to contaminants will be the rim, Glue the two pieces togetherdrilled through to accept connection prevented. High voltage easily tracks to form a plug, Drill a y4-inch holewires. You may add a nut and bolt on along dust, surface contamination. through the plugs center. Cut and in-top for convenience. However, and even finger oil (which contains sert a length of y4-inch (outer diame-beyond about 3,000 VDC this method salt), Also, we shall refer to a "section" ter) metal rod or tubing through thissuffers from point discharge, Metal as consisting of two conductive plates hole, Attach a ball to its top, and sol- Page 6
  • 9. der a wire or small-link chain to its Supply Sources totypes first. The design uses a layered bottom, The wire must make good approach (as shown), and we sug- electrical contact with the foil. Let the All types of plastics: United states Plastic gest using only one section as it is diffi- assembly dry for a day with the cover Corp. 1390 Neubrecht Lane, Lima, OH. cult to align and wrap multiple off, to allow vapors from the rubber 45801; Tel 800-537-9724. Company sections. By contrast, a single section cement to dissipate, then cement the charges for catalog and requires a several feet long is not too unwieldy cover on with silicone or Krazy Glue. minimum-amount order. Write or call them Aluminum foil works great in these for details. Also the internet is loaded with PC-Board Capacitor. Some nifty low capacitors. Youll find the oven/broiler company’s that can supply ever ything you inductance capacitors can be made need. Search for copper, just by typing in type, which is heavy-duty foil, far easi- from pieces of copper-clad epoxy cir- copper metal or copper sheeting, same er to work with than the plain variety cuit board (see Fig, 2), For a simple goes with mylar plastic. Many supply Polyethylene and Mylar are the most two-plate capacitor, you can use one companies will pop up and ytou can then common dielectrics, but you can ex- double-sided sheet. For multiple sec- choose which one you prefer doing periment with other materials. tions, use single-sided board. business with. Looking at the figure, note the ori- To prepare each board, start by entation and shape of the foil plates etching away a 1-inch strip from Small Parts Inc. 305-751-0856 USA (A) and (C), They can be easily se- around all its edges. That process can cured to the dielectric (B) using dou- be simplified by first masking off the Allegro Electronics 203-672-0123 ble-sided Scotch tape. Note also the strip, spraying the bare copper with edge spacing. An outer covering of an etch-resistant paint, removing the dielectric (D) will prevent the finished masking tape, and then etching. capacitor from having a "hot" case, Clean the board after etching, and which might be a hazard. With those rinse with de-ionized or distilled water, When building a large capacitor of points in mind, lay the foil out on a Thoroughly air-dry the sections, or use this type, we suggest that you use smooth sheet of paper, which in turn a blow dryer. Attach strips of alumi- nylon bolts at the corners to hold it all should be laid out on a smooth, hard num foil to each plate. together, The bolt holes should be surface to prevent wrinkling. Carefully If you are building a multiple-sec- pre-drilled before assembly, and all assemble the four layers as shown in tion capacitor, connect the aluminum chips cleared away Make sure the the drawing. Strive to make them flat foil strips together as shown in Fig, 3 and secure them using glue or nylon plate-to-edge spacing is adequate and smooth. bolts at each corner, Spray the for the voltage you will subject the Wrap the capacitor "sandwich" finished assembly wil-h several coats capacitor to. Add extra spacing if you around a non-conductive mandrel or of an insulating product, or paraffin. intend to use bolts at the edges. spool—ideally made of plastic or If you use the dimensions shown in Glue foil carefully to the top of the glass rod (be careful not to break a Fig. 2 and a 0,060-inch gap between first plate using a small amount of glass rod). Try to make the roll straight plates, you can achieve a capaci- spray adhesive, Krazy Glue or RTV sil- and free of lumps and wrinkles. Whentance of 1,94 nF (1940 pF) per section. icone. Press it smooth and let it dry A its all rolled up, secure it with plenty ofWhen deciding on the gap width to photographic finishing roller is handy tape. The author uses clear package- use, keep in mind that the greater the for flattening foil. Repeat the pro- sealing tape for this. Now secure thespace between successive plates the cedure for the second sheet, orient- positive foil tab (assuming its going to lower the chance of arcing, For exam- ing the foil connection tab in the be for DC) to the mandrel using tape,ple, a 1-inch spacing gives you a 30 opposite direction. Keep the plates Finally coat the exposed ends with anlarger gap than a 20-kV spark can and dielectrics aligned as assembly insulating product like silicone RTVjump. Insulation will further improve proceeds, Repeat this procedure for The remaining foil connection tab1hat margin, as many sections as you want. Always may be reinforced by rolling it around keep the final number of plus andThe Stacked Sheet Design. This a small metal dowel, A nail, or a cut- minus plates equal.type is virtually identical to our PC off piece of 1/8-inch uncoated brazing Put an insulating sheet above andboard capacitor, but it can be de- rod is suggested, Apply glue to hold below the last plate and secure thesigned to handle considerably more the assembly together, assembly with nylon bolts. Do not overvoltage. You simply substitute sheet Foil tabs can be strengthened by tighten or the center of the assemblyplastic or glass dielectrics, and glue adding "ribs" of adhesive from a hot will "bow." Finally, clean the ends withaluminum foil in place of the copper glue gun. Similarly the tabs can be a very small amount of isopropyi (rub-for each section (refer to the PC made tear-resistant by applying hot bing) alcohol and wipe dry Smear aboard capacitor drawing in Fig, 3 as glue where they enter the capacitor. coating of silicone RTV over all theneeded). All in all, its an easier design Note most problems with this designto build, as it does not involve the edges. come from particle contaminantseffort of etching copper, and you can Roll-Up Design. The kind of capaci- that stretch a dielectric thin in spotscontinue to add sections to your origi- tor depicted in Fig, 4 can provide where they are trapped by the tightlynal prototype to increase its capacity large capacitance in a small size, rolled dielectric. Another trouble is in-as future demands require. They are a little trickier to make than adequate edge spacing, causing s+acked-section type capacitors, so arcing across the ends, Careful plan- you might want to try a few small pro- ning and assembly will eliminate both headaches, Page 7
  • 10. Make Your Own #HVC1 Copyright 1996 - 2003HIGH VOLTAGECAPACITORS This is a 4,000 volt to 5,000 volt Homemade High Voltage Capacitor, We made this capacitor for our free energy experiments and it worked very well. We used aluminum roof sheeting from a hardware store, we cut aluminum to 4 ½” x 6” sheets and used about 200 pieces. In this design we only used one bolt hole per side, we found that was a mistake, it is far better to have 2 bolt holes per side. Each hole must be drilled on a jig so as to get all the holes drilled in the exact same spot on each piece. If holes are not drilled in the same spot, you will have a large problem when trying to push the + and Negative bolt conductors through the holes. You can not assemble and glue all the negative and positive stacks together and then drill one hole, it does not work we already tried that. The more aluminum plates you stack and add to your capacitor the more amperage your Capacitor will be rated at and will hold. But as an example, if you cut 200 pieces then you will use 100 pieces for the positive side and 100 pieces for the negative side. Cut 10 mil Mylar clear sheeting larger than the aluminum, if you do not your capacitor will arc. But even if it does arc it will not destroy your capacitor you will just see a lot of cool looking sparks going off inside of the clear casing. Make a plywood base with 4 wood dowel rods coming up from the wood base, so you can place each sheet through the rods and down flat onto the wood base, for example: Left rods will be positive, and the 2 right rods will be negative. If you have all your aluminum pieces cut and drilled then begin placing them onto the wood base, first place a positive plate through the left wood dowels and onto the wood base, then spray one piece of precut mylar with spray adhesive, let dry 30 to 60 seconds and then place over top of the positive aluminum plate located on your wood base that you placed down earlier, now spray the top of mylar also and then place your negative plate onto the left dowel rods and down onto the mylar, you will repeat this step until you have one large capacitor stack. Before inserting your metal bolts, place metal washers in between the plates, start with the positive side first then the negative side, you can insert washer as you are placing the bolt through each plate at a time. Optional: You can use 2 bolts and 2 dowel rods, + gets one wood rod and one Copyright 1996 to 2003
  • 11. 10 mil Clear plastic MylarAluminum sheeting Matt Knife Blk Permanent marker, to mark aluminum 10 mil Metal Stopper Clear plastic Mylar Copyright 1996 to 2003
  • 12. Copyright 1996 to 2003 Creative Science & Research
  • 13. Copyright 1996 to 2003 Creative Science & ResearchMarking off your aluminum
  • 14. Copyright 1996 to 2003 Creative Science & ResearchUse a Matt Knife to cut and score your aluminum sheet, You do not needto cut all the way through, score it and then been it back and forth andthe aluminum will break.Although not shown, use a metal or plastic straight edge to follow yourcut.
  • 15. Copyright 1996 to 2003 Creative Science & Research
  • 16. Copyright 1996 to 2003 Creative Science & Research
  • 17. Copyright 1996 to 2003 Creative Science & Research Top View with lid open Side View
  • 18. Copyright 1996 to 2003 Creative Science & Research
  • 19. You will need a drill press for drilling holes.Drill press jig for making precise holesfor each plate, which must be in thesame spot.
  • 20. When finished, bolting your stacks together, use clear silicone caulkingand a card board squeegee to spread and coat the outside of thecapacitor on all 4 sides, Be sure to fill all cracks, let dry for 24 hrs.Doing this will help prevent HV Sparking. Which can be dangerous.WARNING: Never apply High Voltage when capacitor is outside ofit’s protective casing. Always wear rubber gloves.Good luck, and I hope you have just as much fun as we had!Let us know how it goes.Thank youDavid WaggonerCreative Science & ResearchPO BOX 557New Albany, IN.