FICS II Planning and construction

For posts specifically relating to fusor design, construction, and operation.
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Werner Engel
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Re: FICS II Planning and construction

Post by Werner Engel »

Please see: viewtopic.php?f=12&t=10791
I call it a "plasma backdraft restrictor - design ENGEL" ;-)

And it works.
Meaning, that Plasma can't go through such small diameters.

Which additional DAQ did you order? An isolated one? I thought about taking such a device.
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Steven Sesselmann
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Werner,

Thanks for suggestion, the plasma restrictor looks like a very nice idea, but I am now so far down the track with my more complicated system, that I may as well give it a go.

I am getting another identical DAQ NI-6008 it will float next to the MFC, I am using two 18V cordless drill batteries connected with voltage regulators so I get +15V, -15V for the MFC and +5V out for the USB optical end connector and DAQ.

The whole assembly fits inside two stainless steel food trays mounted together.

Steven
Pressure controller
Pressure controller
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Another month has gone by and my F.I.C.S. fusion reactor is near enough to complete, I started the project last January so as far as fusors go that's not bad going. The last month was spent troubleshooting why Labview was crashing as soon as the plasma started flickering, so I have been going over every electrical connection and adding some ferrite suppressors, but the problem was most likely caused by two or three grounding points which were slightly loose. Looks like it's all working now, fingers crossed it will work next time I switch it on.

I also have a small leak which I haven't been able to find yet, it's in the order of 1 micron every 3-4 seconds, and should not be critical for achieving fusion, although I would rather prefer it wasn't there. I consulted with a local vacuum company who said they could send out a technician with a portable Helium leak detector for $1400 per day, so thanks but NO thanks.

Using the labview VI interphase I can now achieve a stable high voltage plasma by setting the turbo pump gate valve to almost closed and allowing the pressure controller to adjust the gas flow into the chamber (see video below).

For those of you who have not been following my build, I am controlling the gas flow with an MKS649 pressure controller, floating at high voltage and driven by two 18V batteries. The pressure controller operates on analogue 0-10V signals, which is provided by an NI-USB-DAQ (also powered by the batteries), the DAQ is connected to an active HUB which in turn is connected to the computer by optical cables. Optical USB cables are now readily available and perfect for this kind of use.

FWIW the MKS Model 649 (10 sccm He) would be perfect for mainstream fusors as well, as it would eliminate the need to manually adjust the chamber pressure, you simply adjust the chamber pressure set point with a voltage source and a potentiometer and there it stays, so definitely worth putting a search on eBay for one of these. http://www.ebay.com/sch/i.html?_from=R4 ... 9&_sacat=0

Floating Gas Supply and DAQ
Floating Gas Supply and DAQ
Below is a 2 minute video showing the reactor operating in a stable plasma mode. As there is no viewport on this reactor I rely entirely on the instrumentation for feedback. Typically I would start with a higher gas pressure and generate a high current low voltage plasma and then gradually decrease the chamber pressure set point until the desired voltage and current has been reached.

https://youtu.be/jB2I23-vR7w
Test Run
Test Run

Now I have ordered two new bubble detectors from our friends in Canada and fingers crossed I will be back with some neutron data soon.

Steven
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Hi Guys,

Just a brief note on my FICS progress.

Bubble detectors arrived and I was hoping to do some good runs, but law an behold as soon as I run the reactor with deuterium the USB fails. I carried out multiple tests with air plasma and had no problems (see video above) but for some reason I don't understand, the remote control system goes down as soon as I vent in some deuterium.

I only get as far as seeing a handful of neutron counts from my sound card detector before the USB goes down which kills the process.

This weekend is a three day weekend for us, so I will use the time for probing, maybe I can use my oscilloscope to catch a spike.

Labview with USB DAQ's are nice, but personally I would prefer analogue control over these high voltage machines.

Steven
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Not sure if I can call this a progress report, because I'm not making much progress, except for in the area of aneutronic fusion ;)

Essentially my machine is complete, everything came together according to the plan, a hollow cathode collider remote controlled from Laview, well almost.

Fibre optic USB connections extending 10 m to my garage allows me to operate it remotely, and after building all the USB hub and DAQ into a copper box for EMF shielding, I can put the machine through it's paces, as long as I use air, and as long as it is not doing any fusion.

It seems to have several modes..

1) High pressure low voltage high current mode, not very exciting and produces no neutrons, I guess it's just like a neon light discharge mode.

2) Low pressure high voltage no discharge mode - obviously no neutrons

3) Medium pressure with intermittent high current discharges and corresponding voltage drops - also no measurable fusion.

4) High voltage (above zener threshold), slowly rising pressure and discharges without voltage drops accompanied by pops in the neutron detector immediately followed by a USB crash (usually the floating DAQ,).
Run data log
Run data log
In the run data above you can see the typical pattern, voltage stable and zenering, pressure slowly rising followed by a fusion event which causes the USB to crash, this immediately shuts off the mass flow controller and stops the reaction, after a few seconds the USB comes back up and pressure starts rising again, and so it repeats.

Unless I can get the USB to stay up at this point I will never get enough neutrons to use a bubble detector, and will never know for sure what's going on.

I welcome any brilliant suggestions at this stage...

Steven
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Werner Engel
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Re: FICS II Planning and construction

Post by Werner Engel »

I talked to people working with remote Controlling in several areas: The told me to use Serial Interfaces between the devices.
People at the University of Vienna are using the following device as a fiber USB Interface (see Picture).

Did you think about choosing different gases to check plasma behaviour?
Helium, Hydrogen?
You can also try to apply a Kind of datalogger (writing data on a Memory Card which you can take out after the incident) inside the Faraday Cage - to monitor USB current and voltage.
And try to increase shielding of the metal box - I'm sure that the seals between the 2 halfs are not RF-tight enough!! There are RF-seals available from several vendors.

Doug was mentioning strage behaviour of DRAM based devices when exposed to Neutron Radiation - I don't think this might be the reason four you fault - otherwise, it would be a great achievement to have that much Neutrons ...

BR,
Werner
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IMG_5678_USB via fiber without ground potential - isolating.jpg
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Steven Sesselmann
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Werner,

It can be more challenging to explain why something does not work, that to explain why it does work ;)

We can exclude neutron radiation as a problem, the few pop's in the loud speaker connected to my neutron detector is just the sound of a sleeping dragon.

I am not sure how I should go about changing to serial connection because the NI-DAQ is all USB based, and putting more USB to serial converters could make it worse?

The part of my setup I don't like, is having one USB hub connected to another hub, this daisy chain connection may cause some instability.

Not sure if packet timing is an issue with one DAQ is floating at -50,000 Volts ? Does this cause a relativistic time delay? I did some quick calculations which indicated there may be a relativistic time delay of 50 µs between the ground based HUB and the Floating HUB, but I am not sure if that would affect the USB signal protocol. If so one would expect the USB to fail all the time when the floating DAQ is at 50kV but it doesn't.

If we look at the plots above I have a short duration 2mA current spike at 50kV which is a short 100W event, I imagine this could generate quite a bit of EMF.

An alternate solution would be to to control the MFC with an analogue potentiometer connected to ground with an acrylic rod, I would then need to build a controller with a stepper motor to remotely control it. Maybe I am taking the remote control part a little too seriously, but I discovered it generates quite a lot of x-rays in certain operating modes, so it feels safer to be at some distance.

Steven

References for USB Optical Extenders
http://www.opticis.com/2011/english/2_p ... 2-100.html
http://www.gigalight.com/products_detai ... d=156.html
https://www.corning.com/optical-cables- ... ables.html

Note, the Gigalight cable from China is USB-A to USB-A and has no copper in the cable, the Corning cable has copper wires to power the USB-B end, not sure about the Optics cable.
Last edited by Steven Sesselmann on Sun Oct 09, 2016 6:49 pm, edited 2 times in total.
Reason: Improvements to my grammar :)
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Re: FICS II Planning and construction

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The moment a fusor or any nuclear accelerator or device has more than 50kv applied X-rays will be the number one health hazard and must be taken seriously. Remote operation is wise and desired. Thankfully, only a microscopic fraction of fusioneers ever see 40kv where shell "shine-through" starts to get serious.

Richard Hull
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Re: FICS II Planning and construction

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Haven't posted any news for a while, maybe some of you who don't know me think I have given up, but the old guys here know that this game is not for quitters.

Have had various setbacks as described in earlier posts, but I am slowly fixing one by one, several delays have been caused by the floating electronics, and I have killed a box full of USB hubs, so I am now in the process of rebuilding that part.

In the mean time my system had an annoying vacuum leak, I could pull a sub micron vacuum with my turbo pump on full speed, but when closing off the chamber it would slowly vent at around 1-2 microns per second, which is not great compared to my earlier chambers. I tried spraying alcohol and blowing helium at the various parts without conclusively finding the leak, so eventually I disconnected the chamber and blanked off the other ports, only to confirm the leak had to be in the chamber.

Those of you who followed my build know that it is an unorthodox chamber, glued together from glass and aluminium with Latex and can't easily be opened. I thought about the problem for a while and eventually decided to try an unorthodox solution. I connected the chamber back up again, pumped down the chamber as far as it would go, and with a big paint brush I slapped Latex milk* all over the chamber so it wetted every joint, and within minutes I could see the pressure dropping. My theory worked, the Latex was sucking it's way into the cavities and plugging up the leaks.

Three days have since passed, the Latex has dried up and the chamber is holding vacuum like never before, the leak is now in the order of 1 micron every two minutes, not bad for a system glued together with Latex and KF Viton seals which has not been baked out..

* Latex milk is a white liquid glue with a consistency similar to milk, it quickly dries to form natural latex rubber.

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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Well it's been a year since I started building this reactor and I was hoping to have some positive results to share with you guys this Christmas, but the illusive fusion dragon remains in the bottle.

It should be pretty obvious for all to see, that I like doing things the hard way, just building a standard 6" fusor isn't where I start (although I might end up there, and Richard will have a good old laugh).

I put together this video to demonstrate that it's not from lack of trying.. https://youtu.be/-58nPYXxIRU

Wishing you all a Happy New Year with plenty of bubbles and clicks !

Steven
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Re: FICS II Planning and construction

Post by Richard Hull »

I would never laugh at any new experiment win or lose. A physical effort in experiment is the highest achievement anyone can attain. Sure, a win is nice, but we learn even in a loss.

I watched and paid close attention to the video...

I would not give up just yet. Your problem in the motorboating within the detector, (massive RF pulse into the detector), tells us you are operating a classic relaxation oscillator much as the now well known NE-2 bulb oscillator made with a NE-2 lamp and a capacitor and resistor which sets the rate of oscillation. The NE-2 gas filled bulb is non-linear and has considerable hysteresis in its on and off points. This is exactly what you are experiencing.

Two things. I assume your supply is really beefy and can easily supply a full 30 milliamps @ full voltage. If not, there is you relaxation oscillator and it will not go away until a really beefy supply is obtained. The next thing is if you are using a voltage multiplier, then that is equivalent to a weak supply unless you are running a very powerful high frequency oscillator into same.
Finally, if you do indeed have a super beefy supply, your ballast resistor may be too large.

The upshot is that assuming a sterling, ample supply at full applied voltage with good current delivery at same, there is always a point where you will and must have a stable plasma in a rarified gas. Finding that point is a matter good gear and practiced artifice by the operator. No two systems will ever function alike unless they are perfect replicas of one another.

99% of all oscillation issues involve a charged capacitor in the circuit where a large enough resistor or a weak supply, (high impedance supply= large resistor), will strike the arc plasma in the gas and imediately the supply will buckle under load. As the capacitor discharges, the voltage plunges, the plasma turns off at reduced voltage, (gas load disappears), the capacitor recharges or the weak supply recovers and the gas plasma fires again and the cycle goes on and on. Classic relaxation oscillator.

All the best in getting a stable plasma. Be it a common old fusor or and advanced FICS design, learning how to operate a plasma gas load system is an art within a hard science background.

Working on a knife's edge........

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Richard,
Your problem in the motorboating within the detector, (massive RF pulse into the detector), tells us you are operating a classic relaxation oscillator
Thanks for feedback and for your diagnosis, I think you are spot on.
Two things. I assume your supply is really beefy and can easily supply a full 30 milliamps @ full voltage.
Not quite a beefy 30 mA, but no chicken either, it's a Glassman 125kV 16 Ma supply, but for this experiment I am limiting it to 62 kV but still with the full 16 mA.
Finally, if you do indeed have a super beefy supply, your ballast resistor may be too large.
This is a valid point, I am using a big ceramic 5 M Ohm resistor as a ballast. The capacitance of the cathode is in the order of 10 pF so with 5 Mohm ballast this works out to a time constant of 50 µs. My calculations estimate the ions moving at 2500 km/s which means the ions travel around 125 m in 50 µs.(more than 200 times longer than the beam return path). A ballast resistor of 10K would cut the time constant down to 200 ns., in which the ions would travel around 0.5 meter. This works out to about a 5 MHz oscillator. What are your thoughts on this?

For the moment I'm just wearing my thinking cap and trying to avoid a complete rebuild.

Steven
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Re: FICS II Planning and construction

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I am now concerned the Glassman is the issue here. 16 ma is nothing at even 30kv and above. At 62kv when the arc strikes you are in need of maybe 50-100ma. The supply auto cuts out or buckles. It doesn't matter which occurs, one or the other will, and apparently, from experiment, does occur!

The 4 meg resistor sounds way too high and 50-100k would be more like it. In the old days unquenched GM tubes used 10 and 100 meg reistors to quench the geiger tube when it fired. I think the 4 meg is doing just that... Still, the supply is also part of the problem.

Try this to check things out. 1. Put in a smaller resistor as noted above. 2. Put in some gas to about 4-6 microns. slowly bring up the supply. If it doesn't strike by 10-15kv, take it back down to zero volts and keep adding gas and keep bringing the voltage back up. Ideally, at some gas pressure you should get a stable gas plasma. Now it is a matter of delicately bringing up the voltage and lowering the gas pressure to keep the plasma lit. Again, it is an art.

Never ever just choose a voltage like 62kv and then bring the gas up. This is doomed to failure and an effective buckling of the supply. I would tend to think 16 ma is nothing in the size device you are working with.

Virginia Commonwealth University, here in town, had a 30kv, 20ma Spellman supply and while they did fusion they could not keep the plasma lit for more that a minute before a burp would auto-shut down the supply forcing them to inch-worm the voltage up again into the fusion region as the current approached the trip point. They have since purchased a much more beefy Spellman and are doing fine. They were working a stock 6" diameter spherical fusor.

You'll not know a thing about FICS success or failure until you get a stable plasma lit in the device and at a voltage where fusion is possible and detectable with your counter or BTI bubble detectors.

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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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Richard,

Thanks for advice, I have a big 10K ballast resistor in stock, so I will give that a go first, and go for the ignition first followed by pressure reduction method.

Hopefully get a chance to try this on the weekend, so I will let you know how it goes.

Steven
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Re: FICS II Planning and construction

Post by John Futter »

Steven
I do not see any potential resistors on your aluminium plates setting the voltage gradient.
Without them you will have little or no focusing ie beaming. see attached pic the resistors are 50meg HV types from Welwyn
DSCN0916.JPG
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

John,

Well observed, I actually had these on my last build, but decided to omit them this time because I didn't think they served much purpose.

My thoughts were that random ion collisions would charge the discs potentials gradually, but that might not be the case.

Relatively easy to fit some resistors all the way down the stack, I can drill small 1.5 mm holes into the edge of the 5 mm disks and push in a copper wire.

In the earlier FICS MK-1 build I used 68M resistors but they got quite hot.

Steven
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Hi All,

Time to post a FICS progress report again, and it's great to have some good news for a change. Since my last post I have implemented the following changes.

Voltage Divider Across the Potential Discs
Taking John Futter's advise, I drilled and tapped small 2.5 mm holes into the sides if the aluminium discs and installed 68 M ohm resistors all the way to ground, much the same way as a PMT voltage divider. The purpose of these resistors is to ensure equal potential between discs, which in turn helps to focus the beam.

Capacitors on last two stages
Richard was of the opinion that my 16 mA power supply might be a bit low on power, so I borrowed another trick from PMT dividers and added some high voltage 10n capacitors across the last 3 stages of the accelerator tubes. My thought here is that it might just store and release a little more energy at times of high current draw.

Large ring magnets top and bottom
To further help ionisation I bought a couple of giant ferrite ring magnets and mounted them top and bottom of the accelerator stack, hoping that the field will extend through the aluminium and into the top of the chamber. Maybe it helps, I don't know.

Invented new flux capacitor
After months of frustration with the floating gas cylinder and gas handling system, I came up with the idea for the flux capacitor, a plasma back flow prevention device that works like an airlock with diffusion pump oil. So I completely removed the old gas handling system and mounted the gas cylinder and the mass flow controller on the rig at ground potential and connected it via the flux capacitor to the cathode with Swagelok hose barbs and 6mm high vacuum hose.

Rewired NI-6008-USB-DAQ
To eliminate any chance of bad connections I rewired all sensors using a boxed telephone style punch down rack and cat5 cables going back to the DAQ, which now sits at the computer end, far away from the high voltage.

First Confirmed Neutrons
The above changes have improved matters and I can now reliably run the machine from my Labview virtual instrument panel without anything crashing, and yes we have neutrons, but I am not yet where I want to be. The flux capacitor breaks down at voltages over 30 kV, it usually starts with a bubble and then a channel opens up through the silicone oil with a beam of plasma shining through the oil. Although this looks incredibly cool it draws a lot of current and makes the oil go brown, so I have now ordered a new flux capacitor from my glass blower which is longer and should hold off the full 60 kV.

Using Labview to detect neutrons
I worked out a crude method of using Labview to detect neutrons by using the sound card as a data acquisition device, but it is not so easy to pick the pulses reliably based on a threshold only, so I use PRA in parallel, but the two counters don't agree. More work to do here.

Practice runs
Last weekend and today I did some practice runs to learn how to drive it, and the typical pattern I am seeing now is that the machine needs a but of warming up before the neutron counter starts popping. I still have a lot of voltage fluctuations as you can see on the attached chart, and this is due to little bursts of plasma through the flux capacitor every time it bubbles. After about 10 minutes tweaking the pressure etc, the neutron detector starts popping, at first sporadic and then more regular, and occasionally it goes crazy for a few seconds. There was a point where I had a real storm lasting around 10 seconds.

My best guess for neutron TIER is in the low 10E+5 range, which at least gives me something to work with.

Steven

Flux capacitor
Flux capacitor
Practice Run
Practice Run
Improved flux
Improved flux
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Voltage Divider
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Hi Guys,

I received the longer flux capacitor last week, it performed better than the MK1 version, at least for the first 45 minutes.

After installing the new plasma backdraft arrestor, I did a long pump down and the chamber was still holding vacuum well, after valving off the chamber the leak was around than 1 micron per minute.

I started the run gently at around 15 micron pressure and gradually decreased the pressure as I increased the voltage. The machine is notably better behaved now that I have the pressure controller and gas cylinder at ground potential. The addition of two large ring magnets top and bottom may also help keep the plasma going.

After allowing the plasma to stabilise for around 10 - 15 minutes, I started seeing the neutron counter move upwards, but then I lost ignition for a moment and had to start again, and at one point the neutron TIER spiked somewhere around 400,000 n/s. At this point something went wrong, and when I went to check the apparatus, I noticed small bubbles coming from the side wall of the glass plasma backdraft arrestor, and on closer inspection there was a hole right through the glass.
Fix Run 19 April 2017
Fix Run 19 April 2017
I feel a lot more encouraged by this latest run and I think a new flux capacitor made from thicker glass should do the trick. Considering I had a steady 150,000 n/s at 30 kV, I have my sights on the mega neutron mark.

Here is my latest Labview VI (Virtual Instrument), from this control panel I control my experiments from a safe 10 meter distance behind a 24" sandstone wall.

Note the addition of a neutron rate meter. From labview I am grabbing the data from the PC Line In port coming from my neutron detector (GS-Neutron-150), counting the pulses and calculating the count rate in software.

Stay posted...
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Re: FICS II Planning and construction

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Nice report and I am glad you got it woking, and makiing decent neutron numbers. Sorry about the hole spoiling you continued running of the system. Back to the repair shop for thicker glass. Keep us updated.

Richard Hull
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Re: FICS II Planning and construction

Post by Dennis P Brown »

Glad your system is/was working and providing neutrons (none too shabby generating 400 k neutrons!); that is a great start but set backs do occur. Doing any real reserach oft (more than most realize) end up like that.

Like the names you use for the system ...I too used a movie name for some of the research work I did in the past; in my thesis I developed a new material (based on glass); while its formal name (laminated Cermet) was used by me in my thesis defense, I did jokingly called it transparent aluminum (in fact, it is 99% glass, but is as flexible and supports superior tensile and strength properties compared to 7070 aluminum alloy.) It is transparent - all of 100 microns ... the committee, however, was most definitely NOT amused at all by my reference ... bad mistake on my part. Not a good idea to make those types of jokes in such formal proceedings.
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Re: FICS II Planning and construction

Post by Richard Hull »

True....When in Rome..... Serious science, in the presence of the properly annointed, must remain, on point, formal, and use SI units; even at formal wine and chesse parties. The talk of fusion has kind of wound down, however, as the shine is a bit off that apple. Political discussion is more in vogue currently.

Science plods along in its usual busy way, as always, once the formality fades. Folks do what they do in day-to-day science. Good science is above formalism, at its core. Formalism is for papers and proper recognition by one's peers when in the presence of other peers.

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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Steven Sesselmann
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

Dennis,

If you want to hide in the chambers of academia and get your papers published and patents granted without proven results you obscure the work with scientific jargon and a "flux capacitor" becomes "silica based plasma current restricting device" but what the heck, if it works no one will care what you called it.

That said, my FICS fusion machine isn't working too well, sure it makes some neutrons but at this stage I still can't compete with a well built fusor. The plasma in my FICS chamber seems unable to stay lit for any length of time. At some point I might swap out the double ended chamber with something more conventional. Other projects are taking priority at the moment.

Steven
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
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Steven Sesselmann
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Re: FICS II Planning and construction

Post by Steven Sesselmann »

CHRISTMAS GREETINGS
First of all a Merry Christmas to all you crazy fusioneers out there, who like me find the festive season to be the perfect time for an antisocial introvert escape into the world of experimental science :)

LONG STRING OF FAILURES
For those of you who are new to the forum I have the most impressive history of fusion failures, mainly because I refuse to build a proven 6" spherical fusor, instead I have tried a whole bunch of crazy designs all well documented on fusor.net over the last 12 years or so. I shouldn't say total failures, because most of the stuff I built actually produced some neutrons but were not the success I was looking for, however I see it as the challenging path I need to navigate to get to the holy grail of fusion.

BACK TO THE DRAWING BOARD AGAIN
The FICS versions described in this thread were disappointing, so I gave it a break for a few months while I tried to understand the problems (essentially a failure of the plasma to stay lit). I came up with an idea which involved replacing the 6" cathode with a much narrower 30mm disc with embedded neodymium ring magnet (see images).

Effectively this new cathode (D10) is designed to operate in conjunction with the adjoining dynodes (D9 andD11) as a low potential ion source. High voltage is connected to dynodes 9 and 11 either side of the cathode, while the cathode is connected to ground via a 50 kV zener diode. (Yes you read that correct 50 kV).

In operation the HV is set to around 55 kV thereby setting up a potential of around 5kV across (D9+D11) and D10, which is a gap of around 10 mm. At the right pressure of around 5 micron the plasma lights up and a 2 mA current of electrons ionise the deuterium gas at cathode potential, which is what I have been trying to achieve all this time. To understand why this is so important you have to read some of my old posts and try to understand my radical ideas about fusion.

F.I.C.S.  chamber cracked open
F.I.C.S. chamber cracked open
Fortunately the Latex glue I use for these chambers is easy to take apart without breaking the glass. Latex dries into a soft rubber compound and can easily be peeled off without any residue sticking to the glass.
New cathode with magnet set in
New cathode with magnet set in
This is the replacement cathode with embedded neodymium magnet. The magnet cost me around $100 online.
New cathode with magnet cover
New cathode with magnet cover
A perfectly machined lid covers the magnet and has a centering ring to help align the disc.
New cathode assembled with Latex glue
New cathode assembled with Latex glue
This is the whole stack put back together with the new cathode, the latex glue can be seen squeezing out. This method requires at least 1 week to dry and preferably with a bit of heat.

EARLY EXPERIMENTS
Early results look promising, and I am making neutrons at super low current consumption. I am measuring the current consumption in a slightly unorthodox way, due to the zener diode arrangement. I calculate the current used as;

(input current) - (output current) = Differential Current

Where input current is the current draw of the PSU and the output current is the current going to ground through the Zener diode. Since the latter can be fully recovered I only consider the differential current * voltage to be the energy consumed.

Before conducting the fusion experiment I calibrate the input vs output current by connecting the HV directly to the zener, i.e. bypassing the chamber, and setting the PSU to 55 kV then zeroizing the differential current.

The data below was acquired from my second run on Christmas eve, and looks promising. If you look at the first 300 seconds my neutron output was in the order of 300,000 to 400,000 n/s isotropic with current draw around 0.5 mA. This is a Q of at least an order of magnitude better than a standard fusor at the same voltage.

But as I said this is very early days and I am operating at the low end of efficiency. According to my calculations the optimal Zener value should be 62 kV which is an easy modification to do.

I see light at the end of the tunnel, is that Q1 I see on the horizon?

Steven
Data acquisition of voltage from Labview
Data acquisition of voltage from Labview
Data acquisition of pressure from Labview
Data acquisition of pressure from Labview
Data acquisition of current from Labview
Data acquisition of current from Labview
Data acquisition of neutrons from Labview
Data acquisition of neutrons from Labview
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
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Dennis P Brown
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Re: FICS II Planning and construction

Post by Dennis P Brown »

As always, excellent presentation using data logging and design details using images of real devices.

When Richard say's to people about novel ideas, that they should build it - you certainly do! And very professional execution, as well.

I assume you feel this design, once optimized, will provide better neutron production by a few orders of magnitude greater still? While that will still fall far short of any goal for a Q = 1 (by still many more orders of magnitude), it would be impressive. So, best of luck and keep up the excellent work.

One thing you might want to look into to is how to create fusion at far higher working pressures in a fusor - some work recently by others here tend to indicate that this type of approach has potential.
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Richard Hull
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Re: FICS II Planning and construction

Post by Richard Hull »

Interesting piece of work and reporting.

Now, if you could just convince the power company to bill you based on the FICS differential power figures...That would be a net gain for you. The 99%+++ of true wasted energy is not being recovered by you, of course. I assume you are talking about a 99%+++ waste thermal recovery system at the one mega-watt input power level.

Dennis put it in perspective. Even with a real total input power of X the net fusion energy is 10e-9(X). No matter how you slice it or try and work the new math into the system, thermal losses remain at 99.999999 % give or take a gain/loss of +/- 0.000009% massive orders of magnitude losses will forever remain.

All the King's horses and all the King's men can't change that in this type of fusion system.

Merry Christmas and keep on pluggin'

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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