Jim Kovalchick -My attempt at smaller fusor

[Jim Kovalchick]

Holiday's for me mean leaving my apartment in Atlanta and getting back to my permanent home with my wife in South Carolina. That's also where my lab is. So, after a long absence I'm back at it.

I've been inspired by all the success with small fusors, so I'm going to give it a try too. Back when my son Mike was just in middle school (he's a PhD candidate now), he and I scrounged ebay for parts for his triboelectric xray generator. We found a working turbo and controller with a lot of misc vacuum parts sold as a lot. The turbo still sees use, but I wasn't sure we would ever use a CF 6 way cross in the pile. So here it is 2019 and the cross is looking pretty good.

I haven't made a grid yet, but I like the single electron axis pipe grids I'm seeing on the forum. The feedthrough is good to at least 30 kV because that's what Mike ran it too. He wrapped the post with several layers of Kapton, and I'm pretty sure it will do 40 that way.

I hope to get it under vacuum by the end of the weekend with Hope's for Christmas neutrons when I'm home next.

Cheers,

Jim K

[Richard Hull]

As Jimmy Durante used to say when other actors appeared to out shine him or appeared out of no where........"Everybody wants ta' get into da' act!"

Richard Hull

[Jim Kovalchick]

Richard,
Well, ink-a dink-a doo.

I love neutrons and when I see Jon R pounding silver to 5000 cpm I want to be all about that even if it means copying.

Jim K

[Richard Hull]

As you can see from my recent post in construction, I am on my way there slowly with my 6 way cross.

Richard Hull

[Jim Kovalchick]

I pulled first vacuum on the chamber this morning. A roughing pump that hasn't run since last winter brought vacuum down into uncalibrated single millitorr in less than 15 minutes. Small chambers are fun. I will eventually put it on a helium leak detector but will wait for all the rest of the connections and valves before I do it.

[Jim Kovalchick]

Even though the current forum problems will probably result in this post disappearing into the ether, I thought I would share my new fusor's first light achieved this morning. My grid is a piece of sheet stock titanium that I formed by beating it around a steel tube. I left a narrow tail on it when I sheared it so I could crimp it to my feedthrough stem. I am not using alumina on the stem because I have found from past experience that it leads to prolonged arcing.

After pumping down the chamber, I set the voltage to -7000 to start and was able to slowly raise air pressure on my chamber using a variable leak valve. Current started nice and low, and I was able to slowly work up the current as arcing subsided. After 10 minutes most arcing was gone.

This was done with air, and I dont expect to use deuterium for some time because most of my swagelok fittings are still MIA from the move.

Jim K

[Jon Rosenstiel]

Lookin' good Jim. Hurry up and find those Swagelok fittings and gaskets.

Jon Rosenstiel

[Richard Hull]

Great work Jim! You've got guts for posting this, for as you note, it could be gone at any moment.

Richard Hull

[Jim Kovalchick]

Okay I'm a little puzzled over this one. My cylinder grid is throwing off beams in more than the axis of the grid openings. Here is a picture of -13 kV and 10 mA with party balloon helium as the feed gas. You can see the obvious at each pipe end but notice the beam coming towards the view port and the other directing orthogonally to the left. Has anyone else seen this with the pipe grids?

The beam coming toward the view port is fluorescing the glass.

[Richard Hull]

Very bizarre. You don't think you have some micro holes in the sheet metal, do you? The near fields in so small a device can get pretty intense. If that keeps up, you will deposit in the center of the view port. What about local heating of the glass? I would watch out for that. If no holes are in the grid it is an amazing thing that one would not expect off a smooth cylinder.

Screen wire placed inside the arm just at the view port would keep the deposition and local heating down I would think .

Richard Hull