New Fusor Project

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Mark Rowley
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New Fusor Project

Post by Mark Rowley » Fri May 24, 2019 12:02 am

After reading about the successes of the 2.75” 4-Way cross fusors, I decided to pattern my next build after Robert Dwyer’s success. As of now, I’m in parts gathering mode and have currently assembled what’s shown in the picture. For vacuum, I currently have a Yellowjacket roughing pump and a Varian HS-2 diffusion pump. Both have been successfully tested on the bell jar Fusor I recently posted about. Deuterium will be supplied by a PEM Cell / Drierite arrangement which I purchased a few months ago. For neutron detection I have a Ludlum 2221 / Remball arrangement, a host of BF3 tubes, and some other odds and ends. HV, like many others is my weaker area. I do have several 70’s era dental type X-ray transformers, a 30kV / ~20ma Universal Voltronics transformer, and a 40kV /7.5ma GHVR supply (needs work). Ultimately, after everything is dialed in, I’d like to try getting a precipitator psu to generate some neutrons.

Aside from needing more fittings and misc hardware, I have a ways to go before getting air plasma in this thing.

Looking forward to the fun and challenges!

Mark Rowley
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Richard Hull
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Re: New Fusor Project

Post by Richard Hull » Fri May 24, 2019 3:43 am

I, too, have thought about giving this a whirl. Still just musing over it.

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.

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Dennis P Brown
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Re: New Fusor Project

Post by Dennis P Brown » Sat May 25, 2019 11:15 am

Sounds good overall - I too have a 2.75 system (complete relative to parts) that I will assemble late fall when I have time - I'm in no rush since I've done fusion. But I was forced to get a new power supply; my old one had to be returned but I really liked it. While only capable of 32 kV, it could handle surges of over 100 ma with no issues. Now the new supply (70 kV) will be lucky to handle its full 15 ma. It will have to be under oil as well unlike my old supply.

Definitely use a proper power supply first (i.e. when everything is all dialed in) - then after generating and detecting neutrons do try the precipitation style supply. Just realize that it is very likely that the Chinese supply will only allow/enable very low level neutron production so a good, proven detector system will be needed.

Creating your own deuterium gas (remember, needs to be super dry) will only supply a very limited amount of gas - so good control of the vacuum system flow rate via a main throttle valve will be essential for the DP to camber so you don't consume your gas too rapidly.

Best of luck and I hope you get your system up and running very soon.

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Mark Rowley
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Re: New Fusor Project

Post by Mark Rowley » Sun May 26, 2019 12:08 am

Thanks Dennis.
I like Rex Allers and Rich Feldman’s idea about using a new, never before inflated, Mylar balloon as a gas reservoir. Once full I can isolate it from the PEM cell cell and connect it directly to either project. And as stated, Drireite will be used.

Being that the PEM cell arrangement is unique, I’ll generate a dedicated post once I start assembling it.

Mark Rowley.

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Mark Rowley
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Re: New Fusor Project

Post by Mark Rowley » Sun Jun 02, 2019 1:27 am

Just a brief update on the project status and my current assemblage of parts. I still need a couple more fittings before vacuum testing begins. So much to do! The big to-do list includes:

Vacuum testing the HV Feedthru and repairing any leaks.
Assembling the HV power supply (inc ballast resistor)
Wiring up voltage, amperage, and vacuum meters
Building the tungsten grid assembly
Assembling the Deuterium PEM Cell and gas collection / handling system.

And of course there is the usual time consuming minutia in the midst of all this.

Mark Rowley
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Richard Hull
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Re: New Fusor Project

Post by Richard Hull » Sun Jun 02, 2019 9:13 am

Looking very good! Slowing to a pace that warrants the best form of assembly and testing in a good and proper order.

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.

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Mark Rowley
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Real name: Mark Rowley
Location: Sacramento California

Re: New Fusor Project

Post by Mark Rowley » Fri Jun 14, 2019 5:48 am

Performed a little more work on the Fusor today. Assembled the chamber, routed the bellows hose to the diff pump, and vacuum tested the system for the first time.

The first problem seen were leaks along the HV Feedthru weld. I halfway expected this so I know what I have do.

After replacing the feedthru with a cf blank )as shown), the chamber did much better but far from where it should be. I’m having issues with the Ritchie 6cfm Yellowjacket. It just won’t pull below 45-50 mTorr on in its own. When I first bought it in 2003 it could easily pull 10 mTorr after about 45 mins of pump time. Overall it has about 25hrs of run time so I’m not sure what the deal is. I’ve vented the ballast for awhile as well as changing the oil. I’ll probably switch over to the 1402 sometime tomorrow until I get this sorted out.

Mark Rowley
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