Grid stem ...plasma where it shouldn't be

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Richard Hull
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Re: Grid stem ...plasma where it shouldn't be

Post by Richard Hull »

Very interesting image. I am glad you got the plasma to be in the right place. See you in a couple of weeks, Jim.

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Jim Kovalchick
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Re: Grid stem ...plasma where it shouldn't be

Post by Jim Kovalchick »

I decided to remove the titanium sheets from my latest fusor. I found that pressure and therefore current runs up too much making the fusor extremely difficult to control. During one run I delicately changed gas flow in with successive adjustments to keep current in an operating range i consider safe for my power supply and grid, and after several minutes I found that I had nearly shutoff gas going in. Outgassing, apparently from the titanium, was sufficient to maintain the plasma current and then some. I am guessing I must have loaded up the titanium from earlier runs. I dont believe this was moisture or nitrogen because the plasma ignition pressure remained much higher than that seen during my air runs.

Removal of the titanium sheets removed this difficult operating characteristic. I did trade one problem for another. Because removal of the sheets exposed the openings of the chamber cross orthogonal to my grid axis, there is a predominant beam. I need to tweak the grid orientation to get more symmetry.

I have attached a couple pictures. The image with only the horizontal beam is higher voltage and lower pressure.

It would seem this fusioneer's work is not yet done.
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20200921_080053.jpg
20200919_170021.jpg
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Richard Hull
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Real name: Richard Hull

Re: Grid stem ...plasma where it shouldn't be

Post by Richard Hull »

This is probably cross related. spheres and long cylinders tend no to see this issue. I have no doubt, you will work it out.

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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