Fusor V construction - the process long running

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Richard Hull
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Re: Fusor V construction - the process long running

Post by Richard Hull » Thu Apr 09, 2020 4:02 am

At some point I will institute a new fusor V construction effort based on a spherical system. This fusor effort is now terminated the kludged fusor III in 2000 did far better at 150kn/s. I'll go with "easy", working the laws of physics to my total advantage. Smooth, even field distribution over a never arcing distance with plenty of absorbing and de-sorbing surface area.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Jim Kovalchick
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Re: Fusor V construction - the process long running

Post by Jim Kovalchick » Thu Apr 09, 2020 12:28 pm

Richard,
I'm sorry to hear about the fruits and lack there of, if your efforts. My numbers are bad now, but they started out fairly good. My original numbers were higher on my pnc than they were when I held it against your Fusor IV doing a million per second. I was originally bolstered and remain so by Jon Rosenstiel's cube fusor success. He stated that his grid size was important, and I will try some more to find the right size and material.

I experienced a lot of the clearance issues you did and sacrificed three Harbor Freight meters, a mini convectron, and a vacuum instrument controller to sustained arcs. It would start with normal grid cleaning type of stuff at new, higher voltages, and occasionally some of little bursts managed to strike continuous arcs. In my previous fusors, the only time this happened was within the path my stem followed from my feedthrough before it entered the open space of the chamber. The good news for me is that all this has pretty much stopped now. Of course it will all start again when I pop my chamber to look into what's going on with my lowering numbers and install a new grid.

I think I will endeavor on a little more. I want to find a grid that wont go to near melting at 400 W. I may look at blanking off my beam ends differently and or try cooling.
Call me stubborn, but I'm not done yet.

Regards,
Jim K

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Dennis P Brown
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Re: Fusor V construction - the process long running

Post by Dennis P Brown » Thu Apr 09, 2020 1:45 pm

I looked into this issue of "smaller" chamber size some time ago and posted the results here in the forum - now, what I mean by smaller chamber wasn't my building a actual smaller chamber but rather (and this is the key) creating a smaller grounding grid. That is, rather then my larger volume chamber walls being the grounding plane, I installed a wire cage inside my existing chamber to create an equivalent "smaller volume".

What I discovered and reported here was that chamber size wasn't the key effect nor was the design of the high voltage supply grid (I used both the same HV grid and chamber.) Rather, when I created a half volume grounding wire cage (reducing my volume by 50%) within the existing chamber, I most certainly did see a 50% increase in neutron counts (measured via a bubble counter so I know it was real.)

The key difference between the two systems (large volume vs. "small" volume) wasn't just a simple volume reduction but rather my chamber operating pressure went from 5 microns (for a stable plasma) to 12-15 microns. My operating voltage/current were also the exact same for both systems. This smaller grounding cage system allowed my deuterium pressure to be greater. Hence, this provided a greater number of available deuterons within the chamber while maintaining the exact same plasma wattage (current & voltage.) The higher deuterium pressure appears to be the key as my experiment clearly showed.

Getting a greater neutron count for identical plasma energy isn't a function of chamber size itself but rather the greater operating pressure one can then create using the identical wattage (voltage and current.) The goal people need to go after is greater deuterium pressure not just a simple smaller volume. If one can raise the chamber pressure for the same energy (voltage/current) than the neutron production will be increased.

(aside; original experiential post: viewtopic.php?f=13&t=12048)
Last edited by Dennis P Brown on Thu Apr 09, 2020 2:31 pm, edited 1 time in total.

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Jim Kovalchick
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Re: Fusor V construction - the process long running

Post by Jim Kovalchick » Thu Apr 09, 2020 2:05 pm

Easier said than done Dennis.

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Richard Hull
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Re: Fusor V construction - the process long running

Post by Richard Hull » Fri Apr 10, 2020 4:57 am

The interesting part of starting over is how do I assemble the new system so that I need not ever touch the fabulous work I did on the entire vacuum system. I want to just remove the cross and plug in the new system. I am so glad I doubled the surface area of the fusor level table. I think the next "new" Thread might be entitled "Fusor V Redux".

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Re: Fusor V construction - the process long running

Post by Maciek Szymanski » Fri Apr 10, 2020 8:10 pm

That's a pity Richard. I was looking forward to your results with the electrostatic ion guns. I was expecting reputable data from a well conducted experiment, as all your efforts. I hope you are planning those with your new V.
“Begin at the beginning," the King said, very gravely, "and go on till you come to the end: then stop.” ― Lewis Carroll, Alice in Wonderland

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Richard Hull
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Re: Fusor V construction - the process long running

Post by Richard Hull » Fri Apr 24, 2020 2:32 pm

Well, I went one arcing scenario too far. I apparently blew out the turbo controller in some fashion. I have the manual with the troubleshooting guide and have verified that all 4 fuses are OK. I also had the 45 volts between the two points noted. I measured at X3 the 15 volts but not the 5 volts and 2volts. As those seem to be triggered in a feedback loop from the pump by a selector '0NE OF FOUR" in a 74c42 which is fed AB from The pump via two J FET CA081 op-amp outputs. I suspected the 74C42. (CMOS blows easy) I pulled it and put in on my lab's bread board system and ran it through the AB sequence and the 0,1,2,3 outputs worked just fine. I sure wish I had a nice schematic of the electronics in the TCP40....

I hope I haven't blown a winding. There was nothing special about the arc. It has happened about twenty or more times while struggling with the fusor V. The pump drops off line normally. I have to hit reset to get the pump start button to work again, and it always has spun right back up. I guess this one broke the camel's back.

When plugged in, the panel lights up the buttons as per normal. I hit reset then the pump on button...It lit perfectly.... the crtical K2 latching relay pulled in then dropped out....no spin up. $%#@*&

I'll keep everyone in the loop. I can see, in the distance, a restoration of the reliable old diff pump and a modified fusor IV back in biz. The turbo has been a joy until it wasn't... I will give it a fair shot and look for a circuit diagram. Anyone here have one??

It is now 10:30 AM here and I haven't slept yet. I'll get some shut-eye.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Re: Fusor V construction - the process long running

Post by John Futter » Sat Apr 25, 2020 6:58 am

It will not be the windings
this from a shelf of US (unervicible) nt 10, nt 13, nt20 etc with a few Edwards turbo controllers thrown in
All from arcs in the early days from the ion source or accel stage system development.
lots of ferrite and TVS diodes later we do not sacrifice to the gods of high vacuum so often!!

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Richard Hull
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Re: Fusor V construction - the process long running

Post by Richard Hull » Sat Apr 25, 2020 7:13 am

John, thanks. It is nice to hear I am not just another VCIW. (now ancient term used by Don Lancaster years ago.....Voice Crying In the Wilderness.)

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Dennis P Brown
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Re: Fusor V construction - the process long running

Post by Dennis P Brown » Sat Apr 25, 2020 6:19 pm

Sorry to hear about the turbo - that is just really not fair; as I posted in another thread about turbo vs. DP I'm even more glad I used a DP instead of my turbo for orginal fusor operation. Never suspected that would occur to a turbo but obviously, it does.

While I used the trubo only for my deuterium project (still sidelined but maybe i'll reconsider if I get my nerve up ... as well as the new facility building I started.)

I use a screen to protect my turbo from stuff falling into it. Now I see that would offer other benifits as wll. So, might be a good idea to always use a screen over a turbo so to act as a Fraday shield. Besides protecting it from objects, should protect it from arcs. I did screen my thermocouple for that very reason and it stopped all arc issues I had with that instrument.

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