[Prev][Next][Index][Thread]

Re: classic demo, and motor modification

Hi,

My son just use our 6.5" coil (15 kV at 180 ma) coil as a senior project at
Cal Poly. During the week or so of demo, I had occasion to help him draw a
crowd for the entertainment of future physics prospects. At one point,
thinking I had control of what I was doing, I picked up our grounded
electrode (on the end of five foot of dry wood rod) and went on to draw an
arc I expected to be about 4.5'. That was ok, but, and the "but" was
important here, unbeknownst to me, someone had removed the earth ground and
tied the thing to the secondary bottom connection.

What actually happened, happened fast and was very entertaining to a whole
room full of professors and prospective students. As I moved near the 7"
toroid, an arc much longer than I expected shot to the electrode, visibly
wound down the stick, down my hand and wrist and out of sight into my
sweatshirt sleeve. From there I can only guess where it went next, so can you
because I ain't tell'in. It was enough that it shot -- still very visible --
out my pant leg and over my rubber tennis shoe and into the floor.
The crowd went wild. Every muscle of my body went wild too. And I know I
scored with the stick my convulsion through across the room. Oh, every
fluorescent in the room came up bright as that spark tried to do things to me
nobody wants done. The clapping was wonderful. I really tried to act like I
knew what I was up too, but -- never again!

Well-done,
Bill Langston

Tesla List wrote:

> Original Poster: Grayson B Dietrich <electrofire-at-juno-dot-com>
>
> Just how dangerous is the stunt of connecting one's self to the
> secondary's output, and letting the arcs splay off rods held in the hands
> or thimbles on the fingers?
> Assuming a reliable system, adequate insulation (mainly distance, I would
> guess) from any ground, and no strikes to the primary, then the actual
> stunt shouldn't be dangerous, right?
> I, and several of my HV-loving friends, would love to try this. Sort of
> like becomming a demigod for a few seconds, eh?
> Seeing how most people don't seem to be doing anything of this sort,
> short of a few advanced coilers in California, then I'm well aware I may
> recieve hardy no-go advice from you listies, but it can't hurt to ask.
>
> BTW- I'd be using a future version ( poly caps, maybe sych rotary) of my
> current coil, which tosses ~36" sparks from a 12000V 60ma NST. And it
> only uses SW caps, with a sloppy RQ-style gap. I hope to achieve an extra
> foot on top of that with rolled poly caps and a better gap. I'm currently
> attempting to modify an induction  motor to AC-synch operation, which
> brings this to my next question.
>
> Is there any easy way of telling if  motor is spinning in synch to the AC
> signal? Would viewing it under incadescent or flourescent lights do the
> trick? I've machined, more or less acurrately, four flats into the rotor
> of a split-phase induction motor, one of 1725 rpm. Will the odd speed
> effect the synching effect? The thingg still runs, but I'd like to know
> if I've succeeded, so I'll use the motor in place of a universal one for
> a rotary SG I'm making.
>
> BTW2- Will 1/2" HDPE be a sufficient material for a rotary disc? It is
> only about 5.5" in diameter. I'm thinking 4 electrodes, spaced evenly,
> with removable stationary electrodes totalling either 8 or 12 at max per
> side. That could give a great flexibility of break rates, ranging from
> the very slow to the very high. It would lend itself to creative
> series/parallel connections as well.
>
> Any comments?
> thanks,
>
> With silent lightning in my hands,
> -The Electrophile-
> Grayson Dietrich
> visit my HV page!
> www.geocities-dot-com/WestHollywood/Stonewall/2509/index.html
>
> ___________________________________________________________________
> You don't need to buy Internet access to use free Internet e-mail.
> Get completely free e-mail from Juno at http://www.juno-dot-com/getjuno.html
> or call Juno at (800) 654-JUNO [654-5866]

--
II*