1-Day Chamber Build

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Raymond Jimenez
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1-Day Chamber Build

Post by Raymond Jimenez » Sun Nov 05, 2006 9:31 pm

Yesterday Jon Rosenstiel and I headed up to Wayne Rodger's place, where Wayne had the idea of building a chamber from scratch in one day, from machining to welding to leak testing.

We used relatively cheap parts, such as stainless steel salad bowls to try and reduce costs, and there was no hemisphere-joining conflat to further cut costs.

It was successful, and the chamber only had 1 leak after all the welds, which was fixed well with a dab of heat-curing epoxy. Ian Hall's (Wayne's machinist) welding and machining skills proved to be up to the test when it came to TIG welding the tube stock to the thin (28 mils or so) bowls. From start to finish he spent 5 long hours assembling the chamber.

If somebody wanted to economize even further, they could probably use KF flanges instead of the conflats!
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Adam Szendrey
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Re: 1-Day Chamber Build

Post by Adam Szendrey » Sun Nov 05, 2006 9:47 pm

Very nicely done! This could fit into a Mythbusters episode lol. How much did the whole thing cost?
There is only one problem with not being able to separate the two hemispheres. It makes it a bit complicated to try various cathode structures. But i see you've made a large opening in the bottom/top ,which is pretty neat!


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Re: 1-Day Chamber Build

Post by wayne » Mon Nov 06, 2006 1:55 am

Flanges and bowls about $100.00.
Ian's labor, priceless.


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Re: 1-Day Chamber Build

Post by DaveC » Mon Nov 06, 2006 7:53 am

Great Job! Elegant simplicity. I will be eager to see the results you achieve, when you're ready to fire it up.

Dave Cooper

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Richard Hull
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Re: 1-Day Chamber Build

Post by Richard Hull » Mon Nov 06, 2006 3:46 pm

Nice project and photo outlay of this work! This not a job for the casual garage machinist or neopyhte weekend welder to be sure. Without the super machinist and welder, the parts would remain only $100.00, but the labor $$$ to hire this level of workmanship would be many times that figure.

Skill and labor qualifications do indeed allow a lot less to be spent in materials. Making an SS fusor still remains a rather costly business for most anyone save a skilled machinist/welder.

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.

David Rosignoli
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Re: 1-Day Chamber Build

Post by David Rosignoli » Tue Nov 07, 2006 2:57 pm

Very nice!

Just one comment. Anytime welding stainless steel it is always a good idea to have good ventilation (forced preferably) and use a filter mask if possible, since you could be releasing hexavalent chromium, which is not a nice metal to be breathing in.


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Re: 1-Day Chamber Build

Post by CanDo » Thu Dec 14, 2006 12:00 am

The thought of using SS food equipment was one of the first things which came to my mind, but I was under the impression that the walls needed to be T H I C K. What sort of pressures will culinary SS bowls withstand (with moderate safety)? Can you go all the way to neutron-cranking with a setup like this, or is it for 'demo' only?

Thanks very much for any input :)

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Brian McDermott
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Re: 1-Day Chamber Build

Post by Brian McDermott » Thu Dec 14, 2006 1:26 am

The maximum pressure ANY vacuum chamber needs to withstand is 14.7 psi. That's it. That's the difference between absolute vacuum and atmospheric pressure. The walls need to be thick in order to witstand the heating effects of electron bombardment, not the pressure. 1/16" is about the thickness of a salad bowl, and 1/32" is about the lower limit. The architectural ornament hemispheres (http://www.sharpeproducts.com) most commonly used here have 1/8" walls and are more than adequate.

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Re: 1-Day Chamber Build

Post by CanDo » Thu Dec 14, 2006 2:03 am

Thanks for the speedy reply Brian. This is excellent news for me, as that budget is a high concern.

EDIT: Just realized that those commercial hemisphere's are much cheaper than I'd thought... Just as well :)

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Carl Willis
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Re: 1-Day Chamber Build

Post by Carl Willis » Thu Dec 14, 2006 3:02 am

The "kit" will come out when some enterprising soul is willing to get an FDA license to sell it, and willing to fend off possible legal challenges from fusor-related patent holders such as Miley and Bussard, depending on what purpose the kit is advertised for and how it is built.

You can bet that such a product, if publicly available, would be sensational and not only in a good way. All of a sudden, large numbers of people with minimal skill or background or initiative would have a free ride to a rather controversial endpoint: a neutron generator. This might initialize a crackdown on the hobby, with news reports like:

"Alberto Gonzales: New kit allows 'freedom-hating Muslims' to brew radioactive material in the privacy of their own homes."

"Consumer Product Safety Commission sues manufacturer of kit blamed for x-ray burns to local [mentally-challenged] teen."

I'm not in any hurry to see a kit on the market.


Geo wrote:
> When does the KIT come out?
> Geo
Carl Willis
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