This Instructable will walk you through building a medium sized Tesla coil.

Step 1: DANGER

Unlike some other high voltage experiments, a Tesla coil's streamers can be very harmful. If you are shocked by the streamers, you will not feel pain, but your circulatory and nervous system can sustain severe damage. DO NOT TOUCH IT WHILE ON UNDER ANY CIRCUMSTANCES.

Also, I don't take any responsibility for you hurting yourself.

This isn't to say that you shouldn't get into high voltage though, its just that if you are planning for this to be your first HV project, its a little to involved. Instead, try out a nice microwave oven transformer, and be safe!

Step 2: Gather the Materials

The total cost came to around $25, being that I already had the wood, Snapple bottles, PVC, and glue.

Secondary Coil:
  • A length of 1.5" PVC (the longer the better)
  • About 300 feet of 24 AWG copper enameled wire
  • 1.5" PVC screw-thing (see picture)
  • 1.5" metal floor flange with threads
  • Spray on enamel
  • Circular, smooth metallic object for the discharge terminal
Base and Supra-base
  • Various pieces of wood
  • Long bolts, nuts, and washers
Primary Coil:
  • About 10 feet of thin copper tubing
  • 6 Glass bottles (Snapple bottles work really well)
  • Table Salt
  • Oil (I used canola. Mineral oil (horse laxative) it preferable as it doesn't mold, but I didn't have any.)
  • Lots of aluminum foil
And a HV power source such as a NST, OBIT, or other transformer that gives off at least 9 kV at around 30 mA.

Step 3: Wind the Secondary

Put a small slot into the top of the pipe to wrap one end of the wire around. Slowly and carefully begin to wrap the coil, making sure that you don't overlap wires or have spaces. This step is the hardest and most tedious part, but taking a lot of time will yield a very nice coil. Every 20 or so turns, put a ring of masking tape around the coil to act as a barrier if the coil starts to unravel. Once finished, wrap a tight piece of tape around the top and bottom of the coil and spray it with 2 or 3 coats of enamel.

  • I built a rig for winding my coil that consisted of a microwave turntable motor (3 RPM) and a ball bearing.
  • Use a small block of wood with a notch in it to straighten the wire and tighten the coil.

Step 4: Prepare the Bases and Wind the Primary

Align the metal stand in the center of the bottom board and drill holes for bolts to go through. attach the bolts tightly upside down. This will allow you to put a base for the primary on top of it. Then bolt the primary's base in. Take your pipe and wind it into a pretty upside down cone (not the flat spiral in the pictures). Then mount it on the supra-base.

Optional was the addition of 2 supports that I zip-tied the primary to.

Forgot to add how to make the spark gap! It is just two bolts in a open-air wooden box, and they are adjustable for tuning, etc. See the last image...

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!

Step 6: Connect Everything

Wire up everything according to the schematic below. The secondary's ground CANNOT be put to mains ground, it will fry everything in your house.

My Coil's Specs
  • 599 Wraps on secondary
  • 6.5 Wraps on primary

Step 7: Start It Up!

Bring it outside for it's first run, as it really isn't safe to run anything this potentially powerful indoors, there is a high risk of fire. Flip the switch and enjoy the light show. My NST, at 9Kv at 30mA, makes the coil give off 6 inch sparks. See it below:

Step 8: For the Future...

There are a few things that I realize I should change in my next Tesla Coil, one of the main ones being the design of the primary coil. It needs to be both more tightly coiled and it needs more windings. Also, i want to make a better discharge terminal. But, I have a new Tesla Coil planned for when i find the time and money, and it will probably be 6-7ft tall!

But for now, I'd like to admire other coilers hard work!
(embedding seems broken, but links work)
<p>the wire getting the spark from the secondary coil , where does it go ? where does conect ? </p>
<p>what is the spark gap for ? , how wide is it ?</p>
<p>If the secondary coil ground is too strong for the house ground ; Where do you conect it ?</p>
<p>Thank`s A Lot ??????</p>
what is enamel spray? why do we spray it on secondary winding??
<p>where did you buy your nst</p>
What is the pvc skrewey thingy for and also what is the flange for and what is a Supra base?
Hiii<br>I will try to make tesla coil<br>I have 800m of 0.5mm wire<br>I will make 1000 turns !!<br>Will flyback transformer have enought power to run tesla coil ??<br>And is 1000 turns enough
<p>Definitely. In this instructable he has 599.</p>
<p>I made it with 1260 turns works very good</p>
<p>looking forward to doing this over xmas should keep the in laws happy!</p>
<p>how do you make the top load</p>
<p>neon sign transformer,</p><p>No one should be building this if they can not Extrapolate and Simplify V = I/R</p><p>I mean come on I know Ohms law, but my maths is rubbish, and I only know basic algebra, but Tesla Coils can kill if you have; a Pace Maker, Epilepsy, history of a Stroke, history of DVT, history of blood clots and they can also cause Asphyxiation due to electrical interference in the respiratory nerves.</p><p>I know enough about Darlington pairs, Brige Rectifiers and Decade Counters to know my way around Electronics, and this is not something anyone should build if they do not feel comfortable with over 200,000 units of IV.</p><p>It is not something I would attempt to build, I already got a shock from installing a new fused circuit in my Mains Fuse Box, I do not care for another.</p>
<p>I don't want to be THAT guy but Ohm's Law is not V=I/R; it's either I=V/R or V=IR</p>
<p>This Tesla Coil isn't going to produce 200,000 W. I do agree though that safety needs to be a priority here.</p>
Keep off your mains box especially if its metal clad. <br><br>Have to agree with you though. I work in Industrial Electrics and some advice/techniques here are....uhm.....dangerous.
<p>The cat looks like the most important part of the project</p>
<p> CHECK THIS OUT 3.5 MILLION VOLTS</p><p>https://www.youtube.com/watch?v=ngiZBaS4Ago</p>
What tools you are using for bending those large copper tubbing???<br>And what the function of oil in these capacitors??
<p>oil as an impurity increases the capacitance. more the amount of impurities in between the plates more will be the capacitance. first study physics, then go on to make such things. &gt;.&lt;</p>
<p>if making the capacitor is not turning out to be a wise thing and if i want to buy a capacitor from the market, what should be the specifications of the capacitor? please tell me in detail. (how many farads etc.). i need to know everything</p>
<p>In my home, power supplied is 230 V, how can I make tesla coil.</p>
<p>Do not play with 230VAC power... you will die lol. Not funny but, try this it's a bit safer and easier. </p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/1SF4KPqNK4c" width="500"></iframe></p>
<p>Thats not a Tesla coil it's a slayer exciter. good video though.</p>
<p>5V USB Portable Tesla Coil<br><br>https://www.youtube.com/watch?v=lZrOns9xqPc<br><br>http://www.ebay.co.uk/sch/shars-stewa/m.html?_nkw=&amp;_armrs=1&amp;_ipg=&amp;_from=</p>
<p>If you want to be eco just use http://inplix.com handbooks</p>
<p>I made it with INPLIX handbooks !</p>
<p>In my home, power supplied is 230 V, how can I make tesla coil.</p>
<p>two things:</p><p>1. buy a step-down transformer that steps the voltage down to 115 v but this would be alittle counter-intuitive</p><p>2. just get a transformer with the same output specs that has an input of 230 v</p><p>The good thing about this project is that it can be inprovised, really, any transformer would work in this project if the output is high enough.</p>
Did this really work
What volt of battery did u used
<p>In my home, power supplied is 230 V, how can I make tesla coil.</p>
whats your capacitor load
Does this actually work to power things?
<p>Not in the way you probably think. It does create very high voltage which can overcome the potential difference between the coils and nearby devices, thereby allowing it to power nearby things. An example of this would be holding up a florescent light-bulb near it. There may be a spark that arcs to the bulb, but you will see it light up. You could also cut your usb charger short for your phone, and make an antena of sorts and put it near enough to the coil, and the power will go through and power your phone. I do not recomend the latter, and I take no responsibility for whether or not you do that...</p>
<p>Tesla himself said te purpose of this was not to have a light show but to bring power to the home. </p>
<p>What does 'NST' mean?</p>
Neon sign transformer. Typically in the range of 6-15 thousand volts and 30-60 milli Amps.
<p>@alarika - try ebay</p><p>Seems a like an older post and not sure if the original poster is around, but a few questions.</p><p>1) It looks like you are using the metal tray as one side of the capacitors, so you need to ensure the aluminum foil around the bottles is in contact with the tray, correct?</p><p>2) Finding NSTs but at 6kV to 7kV. Anything to adjust in the instructions or is it just that the spark is less?</p><p>3) So, how did you ground the secondary if you can't use your mains ground? Did you stick a wire into the literal ground (which certainly could work)?</p><p>4) What is that item on the top of the secondary? Just curious, but I assume it is just placed on top of the PVC with no connection to the coil, or did you attach the enameled wire to that metal 'dome'?</p>
I'll skip question one, as I'm unsure. <br>2) Recommended NST power ratings are between 10-15 kV @ 30-60 mA. Otherwise, the spark gap may not fire at all. <br>3) Using mains ground is not good. Rather than a wire in the ground, most pound a 2-4 foot copper pipe in the ground, and use a thick gauge cable to connect to it. <br>4) The secondary coil's wire is connected to &quot;the metal dome.&quot; Also known as a top load, a metallic dome-like structure is placed on top to act as a capacitor, and a break out point for arcs. It can greatly help increase the arc length.
<p>Where can i buy the NST </p>
<p>How tall is your secondary coil?? My instructor wants to know how tall it is. Thanks!</p>
<p>&quot;try out a nice <a href="https://www.instructables.com/id/Microwave_Oven_Transformer_High_Voltage_Rig/" rel="nofollow">microwave oven transformer</a>, and be safe!&quot; is a bit of an oxymoron. Those things will kill you as fast as anything else. Neon Sign Transformers (NST's) are much better suited for beginning HV enthusaists. </p>
<p>I like your countertops. </p>
<p>hahaaaaaaaaaaaaa it will fry everytjingh in your house</p>
&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>I got similar results. I ended up going with polypropylene. </p>
<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>

About This Instructable




Bio: Devin is a cool guy, eh doesnt kill himself while doing stupid things, and doesnt afraid of anything.
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