Step 5: Build the Capacitors

I decided to go the cheaper route and build a capacitor. The simplest way is to make a salt water capacitor, using salt water, oil and aluminum foil. Wrap the bottle in foil, and fill it with water. Try to get equal amounts of water in each bottle, as it helps to keep the power output stable. The maximum amount of salt you can put in the water is .359 g/mL, but this ends up being a lot of salt, so you can tone down the amount a lot (I used 5 grams). Just make sure that you use he same amounts on salt and water. Now put a few mL of oil slowly into the bottle. Punch a hole in the top of the cap and put a length of wire in it. You now have one fully functioning capacitor, go make 5 more.

Optional: to keep the bottles in order, make or find a metal crate for them

As Glenn781 pointed out below, 6 Snapple bottles with a 15kV 30mA NST can be deadly! If you are using a NST like his, use 8-12 bottles, not 6!
<p>Great Post! What would I need to adjust if I wanted to use a 2&quot; diameter pvc pipe? or 3&quot; for that matter? Thanks!</p>
<p>Where can I find a cheap transformer that works with this?</p>
<p>I found a few of them by putting an ISO request on neon lights with broken tubes (usually transformer is good) you can easily find them 9-12kv</p>
<p>I found a few of them by putting an ISO request on neon lights with broken tubes (usually transformer is good) you can easily find them 9-12kv</p>
I followed the instructions and got the spark gap running for a bit but afterwards the coil would not release any more sparks and im not sure what the problem is so can i get help?
<p>is it possible you shorted it out?</p>
<p>Anything cheap in place of NST or OBIT (tight budget- $15)</p>
<p>What is a more effective tesla coil? Setup A or setup B?</p><p>Thanks!</p>
I have two 9kv nst's with single hv and one earthed to case, can you give us the correct configuraration to use them in a tesla coil.
<p>Can a commercial capacitor be used? if so what would I look for?</p>
Remember that a tesla coil requires high frequency discharges to function, and only pulse-rated capacitors can achieve that efficiently. Do NOT use e-lyt caps or PFC caps for a tesla coil, they will burn out quickly or even worse - blow up. Theggekgroup has a good video on caps for tesla coil use, check that out.
<p>yes of course that's why using bottles is not a good idea. a bottle is simply a large low quality electrolytic capacitor. Ceramic capacitors (which are the ones that I suggested) are for the highest frequencies. I don't think any technology creates higher frequency capacitors</p>
<p>I searched for some high voltage capacitors, basically you have the following for up to 3kV:</p><p><a href="http://www.digikey.com/product-search/en?FV=fff40002%2Cfff8000b%2C340019%2C34001a%2C34001b%2C34001d%2C34001e%2C34001f%2C340020%2C34003e%2C3401b8%2C34049a%2C3800c0%2C380132%2C3801ec%2C38029f%2C3802a0%2C3802a1%2C3802a2%2C3802a3%2C3802a6%2C380306%2C380307%2C38038f%2C38042a%2C3804da%2C3804ef%2C380513%2C380514%2C38054c%2C38055b%2C38055f%2C380560%2C380561%2C380576%2C380577%2C38058f%2C380590%2C380591%2C380592%2C3805e2%2C3805e5%2C3805e6%2C3805e9&mnonly=0&newproducts=0&ColumnSort=1000011&page=1&stock=1&pbfree=0&rohs=0&quantity=1&ptm=0&fid=0&pageSize=25" rel="nofollow">http://www.digikey.com/product-search/en?FV=fff400...</a></p><p>If you need 15kV you can connect five of them in series like this:<br><a href="http://farside.ph.utexas.edu/teaching/302l/lectures/node46.html" rel="nofollow">http://farside.ph.utexas.edu/teaching/302l/lecture...<br></a>but then their capacitance will drop five-fold, so you'll need to connect several such chains in parallel. I managed to find somewhere that the capacitance of a home made bottle capacitor is around 1.8nF <a href="https://www.physicsforums.com/threads/how-does-a-salt-water-capacitor-work.501119/" rel="nofollow">https://www.physicsforums.com/threads/how-does-a-s...</a></p><p>And you can get the 10nF 3kV capacitors on digikey for less than 2 dollars, and on ebay for even less probably.</p><p>the commercially available capacitors that are for up to 15kV are called ultra-high voltage, like this one:<br><a href="http://www.digikey.com/product-search/en?pv14=671&pv14=1425&pv14=1426&pv14=1424&pv14=1398&pv14=672&pv14=1509&pv14=1299&pv14=1510&pv14=673&pv14=1513&pv14=674&pv14=675&FV=fff40002%2Cfff8000b&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25" rel="nofollow">http://www.digikey.com/product-search/en?pv14=671&amp;...</a><br>and they cost 58$ a piece.<br>So. surprisingly, you can't get much cheaper than the home made bottle capacitor, at best you can build one from 3kV ceramic capacitors for 10$ or so.</p>
<p>I've also found these:</p><p><a href="http://www.ebay.com/itm/10pcs-15KV-2200PF-222-High-Voltage-Ceramic-Capacitor-/300678659867?hash=item4601d83f1b" rel="nofollow">http://www.ebay.com/itm/10pcs-15KV-2200PF-222-High...</a></p><p>it seems that there are chinese ceramic capacitors that are not listed on digikey, you can find 10pcs 15kV 2200pF capacitors (each is like a bottle only it won't blow up) for 1.5$ a piece or so</p>
<p>Do you know what is the capacitance of your capacitor?</p>
<p>Some things are in your home already you just have to look..lol dont start ripping pvc out of your plumbing </p><p>addresses shortened for your convenience </p><p>have fun be safe</p><p>the parts not included you can find at your local junk yard and shopping store because they are much cheaper </p><p>pvc pipe (clear)(comes any size so you can get 1.5&quot;) - http://ebay.to/1FsbsfK</p><p>copper enameled wire- http://ebay.to/1KtvyFf</p><p>pvc adapter(1.5&quot;)- http://ebay.to/1JnyM9j</p><p>metal floor flange(1.5)- http://ebay.to/1FsdVXy</p><p>Spray Enamel- http://ebay.to/1LumToh</p><p>Bolts, Nuts, Washers Kit- http://ebay.to/1LuocDu</p><p>10 ft Copper tubing- http://ebay.to/1NKDa8B</p><p>mineral oil- http://ebay.to/1OPlYjg</p><p>lot of aluminum foil- http://ebay.to/1L4fBsH</p><p>hv Power source- http://ebay.to/1KyXOEu</p><p> http://ebay.to/1j7Hxj1</p><p> http://ebay.to/1KyYbPc</p><p>and if you want to use capacitors instead of glass bottles</p><p>http://ebay.to/1NRMjxP</p><p>or even </p><p>http://ebay.to/1V8jcdR</p><p>doorknob- http://ebay.to/1NKM85M (limited) </p><p> http://ebay.to/1FdHaxx</p><p>Happy Generation!</p><p>p.s i hope there is a day to celebrate tesla </p><p>hes awesome</p>
Its really good but it would be better if u focus more on the connections of each parts....
&nbsp;for the love of god do not use 6 snapple &nbsp;jars with a 15kv 30ma nst you will get about 10 min of run time out b4 1 or more blow!!! all 6 were leaking badly. i think ill try a serise/parallel with 12 of them
<p>Why do they leak? Isn't there any way to prevent leakage. Or how you know that caps are leaking?</p>
<p>they would leak at the top of the foil with streamers moving to the lip of the bottle at 15kv</p>
Its easier and more convenient to make a plastic sheet and alluminium foil capacitor.<br>
<p>But as i see from your picture that they are too far for arcing at 15kv if considering that you need 1kv per 1mm to break the air. Anyway is there a way to correct it?</p>
<p>there is far more then 1.5 cm gap! It was do to leaking. When it leaks you will see dim looking feelers bleed from the edges of the foil</p>
HOLY&nbsp;CRAP!!!<br /> <br /> I just fixed the Instructable!<br />
Bro could u help me but explaining how to do that in a video chat
Bro could u help me to do my project
how many volts will one of the snapple bottles produce?
lol!!! good thing you did cause I have 4 litle girls in my house, is it ok if i use 9 small mouth pint jars instead? <br> <br>(i only would have done 3) <br> <br>thanks alot for makeing these instructions. <br> <br>ps i couldn' comment on the right one so this is for DevCoder
Anyone interested in helpin me i just want how to connect all parts
Can i contact u or can u give me a.live video how to make it
Can i contact u or can u give me a.live video how to make it
Can i contact u or can u give me a.live video how to make it
Can i contact u or can u give me a.live video how to make it
I have science fair in my school so i want to make it can u help me but giving guidence how to make it
I have science fair in my school so i want to make it can u help me but giving guidence how to make it
I have a dought u told to connect 8 or 12 bottles right we can connect 6 of them as u shown can u plz tell how to connect 8 or 12 bottles . with picture
<p>What is nst?</p>
<p>No one knows.</p>
<p>neon sign transformer</p>
<p>Please make a tesla coil using 12v.Which is known as slayer exciter</p>
<p>Uhh, now that I look at this diagram again, wouldn't you want the capacitors in parallel with the NST and the spark gap in series?</p>
<p>have you tried lighting a fluorescent bulb? does it work </p>
<p>Finished my secondary winding, does the bottom of the secondary winding wire connect to anything or should I just cut it off flush to my pvc?</p>
it connects to ground.
<p>Thanks, I assume you mean a grounding rod outside or can I use a wire to the house ground?</p>

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