Jim Kovalchick -My attempt at smaller fusor
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
Some interesting and bothersome results. At 38 kV and 10 mA I recorded roughly 750,000 neutrons/sec. I noticed that it appears that my neutron probe saw significantly more neutrons at the lower end of my chamber corresponding to one end of the beam. There were some on the opposite end but not as much.
I also noticed my chamber outgases a lot as it heats up. I think maybe it's my titanium grid.
I did a second run at 38 to 40 kV later today and neutron numbers were way down. Even pictures I took were noticeably less speckled. I moved my gas to throttle ratio to flow more d with no improvement. Hmmm.
I have an idea for a new grid design that does not involve titanium and has only one opening...a cup grid. This will have to wait because it's back to the grindstone for me.
Jim K
I also noticed my chamber outgases a lot as it heats up. I think maybe it's my titanium grid.
I did a second run at 38 to 40 kV later today and neutron numbers were way down. Even pictures I took were noticeably less speckled. I moved my gas to throttle ratio to flow more d with no improvement. Hmmm.
I have an idea for a new grid design that does not involve titanium and has only one opening...a cup grid. This will have to wait because it's back to the grindstone for me.
Jim K
- Jim Kovalchick
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- Joined: Thu Apr 14, 2011 12:00 am
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Re: Jim Kovalchick -My attempt at smaller fusor
With poor results from my last grid I decided on another approach. This time I used a coil of tungsten braided wire. This grid does not make a tight beam, but I'm happy with the proof of concept. Some minor design modifications should fix it.
Jim K
Jim K
- Richard Hull
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- Real name: Richard Hull
Re: Jim Kovalchick -My attempt at smaller fusor
Did you get that twin braided W wire from the "orphan pile" at Midwest Tungsten? I picked up 20 strands a few years back of that double twist wire and it has been the grid in fusor IV for about 5 years. Works great!
I enjoy your reports on your project and the issues with the system. It will help me a lot.
Richard Hull
I enjoy your reports on your project and the issues with the system. It will help me a lot.
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.
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.
- Jim Kovalchick
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- Joined: Thu Apr 14, 2011 12:00 am
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Re: Jim Kovalchick -My attempt at smaller fusor
Richard,
Yes, from the orphan pile. Sadly, it appears that the orphan pile web page is gone. I gave some of my pieces away and still have a few. They are perfect for our work.
Jim K
Yes, from the orphan pile. Sadly, it appears that the orphan pile web page is gone. I gave some of my pieces away and still have a few. They are perfect for our work.
Jim K
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- Real name: Jon Rosenstiel
- Location: Southern California
Re: Jim Kovalchick -My attempt at smaller fusor
Jim,
As to outgassing, was your titanium cathode pure Ti or an alloy? (The one I made was an alloy, 6Al-4V)
Jon R
As to outgassing, was your titanium cathode pure Ti or an alloy? (The one I made was an alloy, 6Al-4V)
Jon R
I like old-timey heavy electronics that you don't have to hold down
with one hand while pushing the on/off button with the other.
with one hand while pushing the on/off button with the other.
- Richard Hull
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Re: Jim Kovalchick -My attempt at smaller fusor
Good Question Jon! I have some 3n6 1/2" rod stock. The alloy sold by many suppliers is to allow for a more machinable product without hampering strength.
Richard Hull
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.
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.
- Jim Kovalchick
- Posts: 522
- Joined: Thu Apr 14, 2011 12:00 am
- Real name:
Re: Jim Kovalchick -My attempt at smaller fusor
Jon, I wouldn't be surprised if it was, but I don't know if the titanium I used was an alloy or not. I bought a small sheet of it at a past HEAS. I think from T.R. Leary.
I'm away from my lab for a while now to check, but I think the sheet had some numbers and/or letters etched on it.
Jim K
I'm away from my lab for a while now to check, but I think the sheet had some numbers and/or letters etched on it.
Jim K
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
Trying yet another grid. This one is a simple piece of stainless tube. Not a lot of neutrons yet.
- Richard Hull
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Re: Jim Kovalchick -My attempt at smaller fusor
Absolutely lovely!! Too bad about the lagging neutron production. I am glad good old fusor IV is standing by just in case fusor V disappoints me. I have just finished mounting my Turbo, (positioning it and bolting it into place). I hope to test it at its head soon. My fingers are a bit numb in the 35 degree lab. If the turbo disappoints, well, I have the diff pump all cleaned and standing by as well. It is all wait and see while giving the system every opportunity to shine.
Jim, I hope your system climbs over time. Hopefully, some wall effect D2 absorption can work its way into climbing numbers in your system.
Richard Hull
Jim, I hope your system climbs over time. Hopefully, some wall effect D2 absorption can work its way into climbing numbers in your system.
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.
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.
- Jim Kovalchick
- Posts: 522
- Joined: Thu Apr 14, 2011 12:00 am
- Real name:
Re: Jim Kovalchick -My attempt at smaller fusor
Thanks for the words of encouragement Richard. I'm sure the numbers will come up. Best of luck with your next fusor. Spring and warmer temps are coming soon!
Jim K
Jim K