Pete put together this pressurized static spark gap - the results are some of the best we’ve seen so far.

This footage shows the advantage of having a phase controller for the synchronous motor. Using the dial we can alter the phase relationship of the motor until it dials in exactly with the up and down swing of the AC supply.

We managed to get some footage of the tesla coil running last night, just before we switched over from a static gap to a rotary gap. It looks like the rotor is not quite in sync with the up and down swing of the AC line voltage. So that’s the next thing to fix.

It’s actually quite interesting to look at the breakout patterns up close, almost like a spirograph…

OK, it had to happen eventually!

Last night I performed the flu-tube test on our coil to see if we had it
tuned at the fundamental frequency - while I was waving the tube up and down
the secondary some sparks jumped and touched the metal end of the tube. I
got a rather unpleasant tingle in my forearm, but nothing more. I was
holding the glass part of the tube.

I asked the guys on the Tesla Coil Mailing List

“Exactly how bad for my health was it?”

Steve,

that’s the million dollar question! There is a guy who does shows by sitting
on top of a tesla coil, the list members probably know of these guys, I
think we are all waiting to see what happens as I understand he has been
doing it some years…

Its a old topic… in theory skin dept isn’t enough to allow the current to
actually pass into your body. So in effect it flows within your skin missing
your internals! though ….. I think the general accepted idea is not to do
it as we don’t really know the long term effects on the body. I for one
think passing high voltage over your skin is a bad idea anyway… Though
people can do far worse things to their skin….

Though some guys do far worse. If it makes you feel any better, when I first
built my coil (over 10 years ago) I had an arc strike me for some time
before I even noticed it and my leg hasn’t fallen off yet…

It possible you could get more static shocks from walking over carpets then
you will get zapped from a tesla coil.. and how many people worry about that
?

my 2C worth….

Chris

Success! I cleaned out most of the burning from the inside of the coil. Then mounted the toroid back on the secondary with a nylon bolt.

I’m also pleased to report that the Tesla tuner I built was pretty much spot on with the tap point of the primary coil…

Well, last night I found out why our Tesla coil isn’t delivering the performance I would expect. I opened up the secondary coil and found carbon scoring on the inside of the coil. Looks like the coil has been discharging internally.

We need to remove the metal bolt at the top and find a way to use a nylon one.

We did the final assemble and checks on our Tesla coil on Saturday night, we rolled it out into the back yard and switched it on…

Nothing is as scary as that first time…

And…

Nothing exploded, imploded, melted, smoked or fried…

We were able to tease 7″ sparks out of the toroid with the safety ‘wand’. We tapped the primary on the recommendation of Teslamap - but we’re not trying to fool ourselves that this thing is tuned. We just built the oscillator tuner based on the 555 chip and we’re going to try and tune it properly.

The static gap is quenched with a tough little AC blower and set to about 0.18 inches. After operating for about 30 seconds the tungsten electrodes did not see very warm at all.

So after getting the tuning as perfect as we can, some of the things we’re going to examine next are:

* Height of the secondary from the primary.
* Height of the toroid from the secondary.
* Spark gap distance / better quenching.
* Addition of a rotary gap. (this is NST based, and so I’m not sure if this is safe…)

Our setup is:

Variac -> RF filter -> NST (12Kv) -> Terry Filter -> Static gap -> MMC (16 series with 10M 1/2 Watt bleeders) -> 0.25 copper tubing primary (15 degrees 12 turns total) -> 4″ 24 gauge wire secondary (19.5 coil height) -> 12″ / 3″ spun toroid.

Jennette Fulda is a fellow resident of the Stutz building. She approached me some time ago to take some pictures for a book she was writing on the incredible weight loss journey she’s been on…

The thing I remember most was when the publisher sent me the contract, it was titled “Half-Assed Photography Contract” (It’s more common than you think)

New York Times Article

I recently received a copy from the publishers, and from Jennette herself - thanks!
I urge you to go check out her blog, it makes for some entertaining reading!
PastaQueen

Now go out and buy the book!!

Last year I covered a wedding at the Sanctuary in Zionsville, IN. The marketing staff got in touch recently to ask permission to use some of the images on the Sanctuary website.

http://www.nanoel.com/page_detail.php?page_id=78&page_type=gallery

I’m in there amongst some of the other images.
It was a great venue, always nice to be able to shoot natural light at a wedding.