Complete Fusor Set-Up

Current images of fusor efforts, components, etc. Try to continuously update from your name, a current photo using edit function. Title post with your name once only. Change image and text as needed. See first posting for details.
Charles Vorbach
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Real name: Charles Vorbach

Complete Fusor Set-Up

Post by Charles Vorbach » Sat Apr 02, 2016 6:16 pm

Hi all.

Here are a few pictures of my complete fusor setup.

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Complete Apparatus

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The Variac and inductive ballast (MOT in primary)

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Chamber and Diffusion pump

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Current and Voltage Meters (HV-Divider not shown)

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PEM Cell Deuterium Electrolysis
I am using a home-made Deuterium Leak (33 ga needle with 35 ga resistance wire).

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Homemade, assembled from fused quartz tubing, OFHC copper, Ultra-Torr fittings

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Paraffin Moderator and a Geiger Counter Tube wrapped in Silver Foil (in the form of Vark - a Indian candy garnish)

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32 kV Deuterium Plasma

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Dissembled GE Dental X-Ray Head

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X-Ray transformer under oil with high voltage resistor and rectifier diodes

Tom McCarthy
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Re: Complete Fusor Set-Up

Post by Tom McCarthy » Tue Apr 05, 2016 10:38 pm

Looks great Charles, congratulations on the progress.

Did you use Richard's FAQ for those HV displays? They seem to be getting a lot of use by members. Also, that PEM cell looks like my own, from a Hydrocar? (think that's the name)

Best of luck,
Tom

Charles Vorbach
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Real name: Charles Vorbach

Re: Complete Fusor Set-Up

Post by Charles Vorbach » Tue Apr 12, 2016 11:07 pm

All credit does go to Richard on those HV displays. The PEM is from an old Hydrocar kit off eBay.

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Richard Hull
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Re: Complete Fusor Set-Up

Post by Richard Hull » Wed Apr 13, 2016 8:13 am

Charles, I have added your name to the plasma club lisitng. Great work.

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.

Charles Vorbach
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Real name: Charles Vorbach

First Fusion

Post by Charles Vorbach » Wed Apr 13, 2016 10:40 pm

Firstly, thank you to everyone who provided the information to complete this project and answered my all-too-frequently naive questions. I can't even begin to list all of diverse subjects I have learned about and problems I have solved in the course of completing this project. I owe a debt of gratitude to everyone on the Fusor Forums.

I am still working on improving my set-up (including achieving star mode), but I believe I have demonstrated fusion and would like to request admittance into the neutron club.

I have several images of my set-up above, including my neutron detector. I borrowed an old Monitor 4 Geiger Counter, disassembled it, and wrapped the tube in silver foil. I am using a paraffin moderator to slow the neutrons to the thermal range, and an Arduino to record the counts.

My chamber welded from 2 6" 304 SS hemispheres, 2 8" CF flange rings, 4 KF40 flange stubs, and 2 2.75 CF flange stubs. An Edwards EO50/60 diffusion pump and Welch Belt-Driven Mechanical pump compose my vacuum system. I restored an thermocouple gauge and placed it between the diffusion pump and roughing pump to ensure my pressure is in the right 'ball-park' during operation.

My high voltage supply is made up of an old GE x-ray transformer under oil. I use a serial string of Microwave Oven Diodes half-wave rectify the output which runs along a 40 kV insulated cable to high voltage feedthrough. I constructed my feedthrough from one 1/2" OD tube of fused quartz, one 1/2" Ultra Torr Union, a KF40 to 1/2" Ultra Torr adapter, a 1/2" OFHC copper round bar 'plug', OFHC bare copper wire, smaller internal fused quartz tube, and a tungsten wire cage. I have voltage and current meters based on Richard's FAQ. I control the voltage from a Variac and have a shorted microwave oven transformer in series act as a ballast.

Deuterium is supplied by PEM electrolysis of heavy water. I add a potentiometer in series so I could control the rate of production and I made a mineral oil bubbler so I can continuously purge the system. I leak the deuterium into the chamber through a 33 ga dispenser needle threaded with 35 ga resistance wire.

All right, on to data. I recorded the beta decay of silver activated by my fusor to demonstrate fusion.

First, I measured the background rate with my detector affixed to the chamber over one 20-minute trial. Using an Arduino to record my counter's pulse-out (5 volt pulse to a 3.5 mm headphone jack), I found the average background rate was 16.2 cpm.

Using my silver activation setup, I exposed the detector in three 10-minute trials. After each trial, I shut off the fusor and recorded the Geiger counter's average counts per minute over the 2 minutes and 30 second afterward (approximate half life of Ag108).

Trial One
Pressure: <10 microns (My thermocouple gauge bottomed out)
Voltage: ~33 kV
Current: ~13 mA
Average cpm after exposure: 20.1 cpm

Trial Two
Pressure: <10 microns
Voltage: ~32 kV
Current ~14 mA
Average cpm after exposure: 20.0 cpm

Trial Three
Pressure: <10 microns
Voltage: ~33 kv
Current ~13 mA
Average cpm after exposure: 19.7 cpm

This gives me an average of 19.9 cpm after exposure compared to an average of 16.2 before exposure. That higher rate corresponds to about 3.7 extra beta particles from the decay of Ag 108.

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Richard Hull
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Re: Complete Fusor Set-Up

Post by Richard Hull » Thu Apr 14, 2016 4:03 am

Try repeating the runs, but count for only 1 minute as the bulk of your radiation is off the shorter half life silver that lasts only 54 seconds. As you count longer you count will average out lower.

I see your metered GM counter is one that uses the tiny little LND512 tube. Is that the one you are counting with and sending to the arduino or is there another tube in the moderator. We need a ton of more details on the detection method. maybe some detailed images of the silver wrapped GM tube, etc.

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.

Charles Vorbach
Posts: 45
Joined: Tue Oct 14, 2014 10:39 pm
Real name: Charles Vorbach

First Fusion

Post by Charles Vorbach » Sat Apr 16, 2016 11:40 pm

Here is a more detailed overview of my detector set-up. Here is a link to the sketch I am using with the Arduino: http://vorbachblog.com/files/GeigerCounter.ino

So I started out by disassembling my Geiger counter.

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It does use a really small LND512 tube.

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I removed the tube from the from the rest of the counter then soldered on longer leads.

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I wrapped the tube in tape sticky side up and then rolled it in silver foil.

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Then I wrapped another layer of tape around the tube, sticky side down.

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Then I hollowed out my moderator block.

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I taped the tube inside to get my counter.

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Here is my neutron counter.

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Here is the whole neutron counter apparatus and Arduino. The Arduino plugs into the 3.5mm headphone jack and long USB cable runs to my computer so that I can start the sketch when I turn off the fusor.

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I ran another 10 minute run today, but this time I only had the meter count for 1 minute. This did produce a bit higher count.

Trial One
Pressure: <10 microns
Voltage: ~33 kV
Current: ~11 mA
Average cpm after exposure: 22.1 cpm

That works out to 5.9 counts attributable to the beta decay of silver.

Please let me know if I can provide any more information.

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Richard Hull
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Re: Complete Fusor Set-Up

Post by Richard Hull » Sun Apr 17, 2016 3:37 am

I am satisfied. While the count is low for such a high fusor voltage and current level, the LND 512 is a very low volume tube and not a lot of counts could be expected from it..

I have logged you into the fusioneers club listing. Good work on dragging the result out of a system that was cobbled up on the detection end.

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.

Dan Knapp
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Re: Complete Fusor Set-Up

Post by Dan Knapp » Sun Apr 17, 2016 6:41 pm

Is it feasible to count silver activation beta radiation with a metal wall Geiger tube? I was under the impression that silver activation analyses were normally done by scintillation counting or by use of a pancake counter or mica window Geiger tube. This experiment seems lacking the usual control of making a measurement with and without moderator. Shouldn't the background measurement be from a fusor run without the moderator followed by counting?

Charles Vorbach
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Joined: Tue Oct 14, 2014 10:39 pm
Real name: Charles Vorbach

First Fusion

Post by Charles Vorbach » Sun Apr 17, 2016 10:47 pm

Thank you so much. It is an honour to be part of such a select company.

I will try to continue to improve my set-up and detector. I hope to produce much higher neutron counts in the future.

As I am 17 and I am currently attending Bronxville High School, would it be possible to place my name under high-school achievers?

Thank you so much again to everyone who helped make this project possible. This has been a fun, challenging, and educational journey, and I hope to continue on it in the future.

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