Ion gun construction questions

For the design and construction details of ion guns, necessary for more advanced designs and lower vacuums.
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Ion gun construction questions

Post by mikecavett520 » Thu Aug 14, 2008 1:35 am

Hi, I am new here and I have spent some time reading the literature involved in creating a fusor, however I am still wondering how cheaply a decent ion gun can be assembled (one capable of supplying enough ions for at least minimal fusion).

I am on an extremely tight budget and I have no machining/welding experience (yet).

So, short of laying everything on a silver plate for me... what are my options?

Any help is greatly appreciated!

- Mike

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Steven Sesselmann
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Re: Ion gun construction questions

Post by Steven Sesselmann » Thu Aug 14, 2008 8:28 am


Welcome to the group

In regards to your question, I assume you realize that an ion gun is not essential for a standard Farnsworth fusor to work. In fact some of the best amateur fusors in this group run by ionization that occurs naturally in the steep electrostatic gradient between the cathode grid and the anode.

In saying that, many have built and are building fusion reactors with ion guns (me included). Most of them are home made and have probably been done on small budgets.

There are several ways to ionize a gas, using electron beams, RF or even microwave.

The easiest method is probably to use a hot filament to emit a cathode ray, you then pass your gas through the cathode ray, thereby ionizing the gas. The ions are then extracted through a small aperture towards your target.

You should find plenty to read in this forum about ion guns.

Good luck..

Steven - Gamma Spectrometry Systems - Various papers and patents on RG

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Richard Hull
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Re: Ion gun construction questions

Post by Richard Hull » Thu Aug 14, 2008 1:35 pm

Steven's points are sage.

A decent ion gun is tough to make. Ideally, you want four or more in a fusor of the classic Farnsworth type.

As money is tight for you, you need to forget ion guns, assuming you really want to get on with fusing or doing real fusion. These are an amusement that not one person has worked in a fusor beyond a single such item in experiment, to my knowledge.

This said, there will be plenty of time for ion gun building after the rush of success with a simple fusor gives you impetus to forge onward and upward.

With not much money, slow and steady, and in stages, is the way to proceed.

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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