Greetings,
This is M.SHAMSUDEEN from INDIA. I started building my fusor a year ago and I am almost close to getting it done . I have run into some issues and i want someone to help me with .Many from this forum have helped me in the past and i am grateful to them. I have attached images and questions along with it please do feel free to suggest.
POWER SUPPLY
I am using a x ray transfomer which can out put 100kv @100 milliamps. i haved wired my transfomer as per the circuit diagram in the forum
everything is made as per the circuit diagram. A variac is used to control the input voltage along with a mot.
The whole system is under oil with a decent vaccum. So my question is, Do i need to do anything other than this before turning on the transformer?
FUSOR AND VACUUM SYSTEM
The fusor is a 6 inch ss chamber with cf flanges. i have attached a hv ceramic feed through, a view port,a pirani gauge head and a penning gauge head , copper tube for deuterium flow in a cf flange
I am using a 4 inch diffstack model water cooled diffusion pump. I tested my system . i got my pirani gauge working and it maxed out (crossed 0.001 m.bar) when i turn on the penning gauge it kind of fluctuates and its not showing steady reading
so the question what is causing the penning gauge to fluctuate? is it due to a vaccum leak or gauge fault.
GAS SUPPLY
The D2 Gas is supplied through a two stage hydrogen regulator in series with a needle valve, A 20 feet copper tube(2mm diameter) is then used to deliver gas from the needle valve to the fusor
so the question is this system enough to deliver gas ?
GRID
At first i though of using tungsten grid (1mm), but when i tried to spot weld it kind ah broke . so i made the grid out of 2mm thick nichrome wire. it hold up pretty well.
so the question is it safe to use nichrome grid for fusor operation?
apart from these if you have any questions regarding the build please feel free to ask.
PROGRESS AND FEW QUESTIONS IN FUSOR BUILD
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Re: PROGRESS AND FEW QUESTIONS IN FUSOR BUILD
a penning gauge that fluctuates is usually dirty inside
try tapping the gaugehead does it respond to the mechanical input??
try tapping the gaugehead does it respond to the mechanical input??
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Re: PROGRESS AND FEW QUESTIONS IN FUSOR BUILD
Greetings John Futter,
I tried tapping the gauge but no result, however i found the penning gauge needle fluctuating even when not connected to fusor. what might be the problem? any suggestions?
I tried tapping the gauge but no result, however i found the penning gauge needle fluctuating even when not connected to fusor. what might be the problem? any suggestions?
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Re: PROGRESS AND FEW QUESTIONS IN FUSOR BUILD
Never power up a penning gauge when at atmosphere
doing this will immediately pollute the internal electrodes
only power up when your pirani bottoms out
it is also possible to hurt the high voltage electronics in the meter unit by trying to draw too much current wsith the gauge head internals arcing
doing this will immediately pollute the internal electrodes
only power up when your pirani bottoms out
it is also possible to hurt the high voltage electronics in the meter unit by trying to draw too much current wsith the gauge head internals arcing
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Re: PROGRESS AND FEW QUESTIONS IN FUSOR BUILD
please Advice where did you get the HV ceramic feed through
- Richard Hull
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Re: PROGRESS AND FEW QUESTIONS IN FUSOR BUILD
The X-ray transformer is ideal. Is it center taped? Most are.
The only reason most can't seem to find them is their world is limited to the internet. Few true scroungers exist today. The thought of stumbling out in the real world is abhorrent to them. So they can't find them. Fine, I have no issue with that at all. You obviously went out there. The FAQs contain info on updating old x-ray transformers. If they have PCBs in them leave that oil in them. Do not replace that oil it is perfect as is.
I have dipped my bare hands in PCB oil for years. It is safe. DO NOT let it catch fire or reach kindling temperature! That is when dioxins are generated. In all high power utility transformers this is a possibility that you will not suffer running a fusor at a tiny fraction of the capability of the transformer. You have a proven, near bullet proof, fusion power system if wired and worked with properly.
If center tapped and you full wave rectify against ground with no filtering, you will have a 120 hz DC peak 63kilovolt supply. Filtering this DC will improve the time at peak DC level. Filtering will make the system deadly due to stored energy. However, all HV DC power systems capable of running a fusor are 100% deadly.
I speak to your supply only here and not the system as presented. Others will comment. Pull some sort of vacuum before turning on your vacuum gauge. No need to even think about starting a diffusion or Turbo pump until your entire system is below 40-50 microns. lower is preferred. All in the FAQs here.
Richard Hull
The only reason most can't seem to find them is their world is limited to the internet. Few true scroungers exist today. The thought of stumbling out in the real world is abhorrent to them. So they can't find them. Fine, I have no issue with that at all. You obviously went out there. The FAQs contain info on updating old x-ray transformers. If they have PCBs in them leave that oil in them. Do not replace that oil it is perfect as is.
I have dipped my bare hands in PCB oil for years. It is safe. DO NOT let it catch fire or reach kindling temperature! That is when dioxins are generated. In all high power utility transformers this is a possibility that you will not suffer running a fusor at a tiny fraction of the capability of the transformer. You have a proven, near bullet proof, fusion power system if wired and worked with properly.
If center tapped and you full wave rectify against ground with no filtering, you will have a 120 hz DC peak 63kilovolt supply. Filtering this DC will improve the time at peak DC level. Filtering will make the system deadly due to stored energy. However, all HV DC power systems capable of running a fusor are 100% deadly.
I speak to your supply only here and not the system as presented. Others will comment. Pull some sort of vacuum before turning on your vacuum gauge. No need to even think about starting a diffusion or Turbo pump until your entire system is below 40-50 microns. lower is preferred. All in the FAQs here.
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
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