Thursday, May 20, 2010

Artificial Fulgurites

Many months ago while browsing youtube for crazy stuff people do with electricity, I stumbled upon this crazy guy making fulgurites with what looks like 4 microwave over transformers and a couple capacitors wired together.

I also found these guys using some insane 12 kV at 1.3 amp power supply.

And this guy with a 12kV 600mA supply he constructed out of a bunch of microwave over transformers that he keeps sunk in mineral oil. (melting sand into glass inside a cardboard box).

So once we got the pole pig running with a space heater as a resistive ballast, I had to give it a try. We tried "play-sand" in plastic buckets, and eventually moved up to quartz sand in terracotta pots. Here is a short video of the process:

The Pole Pig

In mid December 2010, the HBL mailing list got this email:

Subject: Big, high-voltage transformers for sale.

I've collected a number of big high-voltage transformers over the last few years, hoping to kickstart a large Tesla coil project. Alas, work and other hobbies have taken over, and so it's time to liquidate some coiling assets. Hopefully, when I have more time on my hands, I'll be able to make some sort of comeback.

For sale (pickup only!):

* Cooper 10kVA 34.5kV two-bushing pole transformer with tap changer and lightning arrester. A rare, very high-voltage unit. Big! Weighs about 700lbs. Never used (for anything); looks like new. (Here's the transformer with me for scale) Asking $400 obo.

* Westinghouse 2.5kVA 15.6kV single-bushing potential transformer. Oil-filled! Old and big. Nearly 500lbs. Asking $150.

* GE JVT-200 3kVA 24kV "Super Bute" two-bushing potential transformer. Resin-cast. This would make a super transformer for a medium Tesla coil. Asking $150.

The picture above is the the Cooper and its seller.

The HBL thread was only 8 replies deep when we had assembled the cash necessary to purchased the Cooper. The thread eventually grew to 64 replies and it covers the range of arranging picking it up, to discussing how to hell we're even going to use the damn thing, to what the hell we're going to use it FOR. Ideas ranged from charging the quarter shrinker, to powering a home-brew LINAC, to making toast.

I missed pickup, delivery, and all of the early shenanigans with the pole pig because of my trip to India. But I did get to ponder what to do with the new high voltage transformer while sitting around in Buddhists temples in India. Safer faster quarter shrinker charger, artificial fulgurites, and an HV lifter were at the top of my list.

Wednesday, May 19, 2010

Violet Rays / Violet Wands

So about a hundred years ago when people first started figuring out how to manipulate electricity, someone got the brilliant idea that if you applied electricity to the human body just right, it could fix... well... anything. In the 20's-40's there were a great number of Violet Wands or Violet Ray devices built.

Turns out, they don't cure cancer, but they do stimulate blood flow in an area. So anything that's helped by improved blood flow can be helped with violet wand stimulation. This includes improving hair growth, skin quality, and a few other minor things... Its like applying a heating pad... except different.

The problem was they people selling these things were claiming they would cure cancer, and any various body-part-itis you could think of. So when the FDA got teeth, many of these companies went out of business. Seems like the only modern versions being built and sold are "neon sign testers".

Fast forward a couple decades and these days, violet rays are used for science demonstrations, historical quack medical demonstrations, and by the BDSM community for various flavors of sensation exploration.

Most of this I knew, I'd just never seen one in real life. Then one night, hanging around the lab (after midnight), I noticed a strange looking... device sitting on the table. I asked what it was. Several people chuckled, someone yelled: "We have a volunteer!" and its excited owner popped their head into the room.

As I had anticipated, I was totally into them. So I started buying vintage rays on Ebay. Some were broken, some worked, but were kinda sketchy/scary. So I started repairing them.

First were the easy ones. They worked, they just had scary, old cables. Ninety year old wax impregnated cloth wrapped copper is not something I trust to protect me from high voltage. Swap out some cables with some modern cloth cables (made to look old for antique restoration). And they rays still worked. Sweet! I upgraded the safety of a vintage ray, and didn't break the thing. That was a moment I was proud of.

Then I had a broken ray, and I was pretty sure it was a dead capacitor. So I did some estimation of what kind of capacitance I probably needed, bounced some ideas off my buddy Rob, and because I was familiar with the use of Deep Fried Neon's MMC Calculator; I was able to figure out how to build a couple different capacitor's MMC in the range I was looking for. So I ordered a bunch of ceramic capacitors from China off ebay. Soldered my MMC, removed the 90 year old wax-paper-aluminum-foil capacitor, and connected mine into the circuit. When that ray came to life... that was a categorically different moment. Resurrecting an electrical antique from the dawn of the electrical era with parts from China purchased off ebay. Yeah, that ruled.

Tho it turns out, its too hot. Modern ceramic capacitors discharge so much more quickly than their 90 year old counterparts, so they ray ends up being too sharp. I have some more experimentation to do with chokes and other options to vary the circuit's output.

Somewhere along the way I realized I'm beginning to intuitively feel the difference between high frequency and low frequency. Between the 5-10 mA range, and the 50-100 mA range. Between 60hz and a few khz. Its hard to explain, but its pretty awesome.

So yeah, if you're having a party, lmk if you want me to bring the electricity. At this point, I have about 12 violet rays. I don't honestly need that many. Let me know if you'd like to buy one. I know a great deal about them, and we can find one that suits your interests.

Wood Burning Fractals

During the research for my Tesla Coil, I spent a lot of time browsing around the very excellent site Tesla Down Under.

There I stumbled upon Peter Terren's wood burning fractals experiments.

That looked like a lot of fun, and I had recently acquired an NST for my tesla coil, so one evening with my good friend Servo, we burnt some fractals into some wood.

I ended up throwing away all the pieces of wood I burned when I moved, but it taught me a lot about high voltage generated fractals... obscure, abstract knowledge that ended up helping me later making 3D fractals melting moist sand into glass.

Thursday, May 6, 2010

Tesla Coils

After playing with Rob's Tesla coil at Toorcamp, and catching some lightning off of it back at the lab with the Sword-of-Power and Daggar, I decided to build my own Tesla Coil.

Winding the secondary coil took most of the night, but Chicken was kind enough to let me use his coil winder:

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Eventually, I got it up and going:

TeslaCoil 01

To commemorate my success (and to help me remember how to put the thing together), I got a tesla coil wiring diagram tattoo on my left forearm.

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One night, Rob, Chicken and I all setup our coils. Bill Beaty brought a pony-keg of argon, and we had fun playing with fire and lightning.

Updated: I dug up the specs off the wiki:

--Parts list and specification--

Starting with Rob's BasicTeslaCoil as a default, I ran my own numbers.

Here are the parameters my (still in progress) basic coil. I crunched the numbers using Deep Fried Neon and Wolfram Alpha and TeslaMap.

15 kV Neon Sign Transformer (NST) from Berry Neon:
15000V * 0.06A = 900W supply

Ideal spark Length (inches):
Deep Fried Neon says L = 1.7 * sqrt(900) = 51"sparks.

Maximum cap size math:
60 Hz, 15000V, 60mA = 0.0106uF cap max.
Rob read somewhere that coilers multiply that times the golden ratio. 0.0106uF * 1.6180339887 = 0.01715uF

Actual cap size math:
8 x .15uF 2kV HV capacitors = 0.0187uF rated at 16kV

Secondary coil:
5" diameter acrylic, 20" coil, (4 to 1 ratio @ 5") 28 AWG wire (0.0126 bare, 0.0137 inches including insulation.)
Coil length is 20" using 1860ish feet of wire. And about 1424 turns. Inductance is 57 mH, capacitance is 8.5 pF.

Top load:
Teslamap says "Optimum Top Load Cap" = 17.09 pF
Toroid: 4" Ring Diameter & 16" Total Diameter = 17.4 pF
Sphere: 12" = 17 pF (I ended up going with a sphere)

Resonant Frequency:
130.9 kHz - Needed Primary Inductance 49.7 uH

Primary coil:

Should be 49.7 uH Based on 12 AWG : Primary Coil Wire Diameter: 0.0808 in Primary Coil Wire Spacing: 0.03 in Primary Coil Hole Diameter: 7 in Primary Coil Incline Angle: 90 deg

TeslaMap tells me I want 13 or 14 turns of this. 13 turns = 45 uH 14 turns = 51 uH

(For anyone interested in Tesla Coils, I highly recommend spending a whole bunch of time poking around with the DeepFriedNeon and TeslaMap calculators. Its taken me several weeks of saturating myself in the concepts before they're starting to make sense.)

Monday, May 3, 2010

Shrinking Quarters

Before I started hanging out with the folks at Hackerbot, they had built a coin shrinker and brought it down to Makerfaire, where they took some amazing high speed video (more details over at Intellectual Ventures Lab's website).

Apparently my dear friend, and high voltage mentor Rob had a great deal to do with it, but he's quite humble speaks only to the contributions of the rest of the Hackerbot folks who helped like Chris and Chicken and Dan many others... I'm not even sure who, It was all before my time.

When I started hanging out regularly at lab nights, I showed curiosity and aptitude and I became a competent operator of the coin shrinker. Sometimes I feel like someone must have made some terrible mistake to let me (of all people) play with such an incomprehensibly potent and dangerous device... then I feel every stranger when everyone in the room is asking me to explain how it works.

The coin shrinker is quite simple. Its a gigantic capacitor we charge up, then discharge into a coil: 12 windings of 12 gauge, with a coin in the middle. All the energy we just dumped into the coil creates a tremendously powerful magnetic field, which in turn causes another (opposing) magnetic field in the coin. The magnetic forces cause the material of the coin rush to the center of the field at something like 400 miles per hour, for 40 micro-seconds. Then the coil explodes/vaporizes inside the blast chamber.

Very simple. Could kill you to death if you touch it wrong when its charged. Good stuff. Crazy dangerous.

At some point the TV show Time Warp tried to take high speed video of quarter shrinking. They missed the shrinking event.

From the 100,000 fps video taken by Intellectual Ventures and Hackerbot at Makerfaire you can see at 1:03 the shrinking event occurs, and is done. Then the explosion happens:

In the Time Warp episode, the first frame they show (about 1:10) is explosion. They missed the event. They were shooting at 100,000 fps same as the original Makerfaire Hackerbot shoot were using.

This inspired us to shoot again, and try for a higher frame rate. Nathan showed up with a sweet light ring he'd built. High speed photography requires very very bright light. We got some amazing video that night at increasingly high frame rates. The prizes of the night were the euro and quarter at 180,000 frames per second.

These videos are really boring after the white flash in the 6th or 7th second. Its all about rewatching those first few seconds, and pausing judiciously.

We gave the shrunken euro to some hackers visiting from Europe. I still have that quarter.

Getting started Cooking with Lightning

To tell the story of Cooking with Lightning, I need to start off by talking about HBL. In the summer of 2009. I was interested in going to Toorcamp to visit an old Titan-1 missile silo & I needed to arrange a ride. My friend Willow was getting a ride with Baron, and camping with Hackerbot Labs.

To make sure the HBL folks and I got along, I was required to go hang out at the lab on a Saturday night to get to know the crowd I'd be camping with. We hit it off quite well. I had a blast at Toorcamp, and I've been a regular at the lab ever since.

Hackerbot Labs at ToorCamp 2009 from Rob Flickenger on Vimeo.