Restarting Efforts on Demo Fusor II

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John Futter
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Re: Restarting Efforts on Demo Fusor II

Post by John Futter »

IMHO
milking rubber is much better --it also gives much better vibration isolation from the backing pump
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Rich Feldman
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Re: Restarting Efforts on Demo Fusor II

Post by Rich Feldman »

Kuri is the same brand as my spiral hose.
John's a practiced expert with vacuum stuff, and I'm lately just a pretender. Have never set up any diffusion or turbo pump with a backing pump. Need to clear a path to a work space for vacuum gear, not touched (except for opportunistic acquisitions) in about 10 years.
[edit] I was successful using same kind of hose in 1" ID, for the project that brought me to fusor.net in 2010.
viewtopic.php?f=10&t=3977&start=10#p25528
Last edited by Rich Feldman on Sun Sep 13, 2020 6:39 pm, edited 1 time in total.
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Ed Meserve
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Re: Restarting Efforts on Demo Fusor II

Post by Ed Meserve »

John,
Rubber hose like this? :

https://www.qcsupply.com/120312-epdm-se ... -4-id.html
3/4" Rubber Hose
3/4" Rubber Hose
Ed Meserve
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Dennis P Brown
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Re: Restarting Efforts on Demo Fusor II

Post by Dennis P Brown »

The key to a useful foreline pipe is that it not collaspe; the vacuum level (as long as plasticizers aren't an issue) capablities are not terribly critical.
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Richard Hull
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Re: Restarting Efforts on Demo Fusor II

Post by Richard Hull »

Over the years, I have used them all, but personally prefer the red india rubber sold by many vacuum dealers. It will not collapse as they sell it only in wall thicknesses which will not allow that to happen, based on bore and outer diameter. Early on I used the heavy black threaded auto water hose. It never collapsed. For a long time I used the steel internal coil steel reinforced tubing, but in 2004 switched to the red rubber. (I have seen it in white as well).....As always on the fore line try and keep the line under 1 foot long. Fusor V uses an 8-inch length of the red rubber from Duniway.

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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Ed Meserve
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Re: Restarting Efforts on Demo Fusor II

Post by Ed Meserve »

All puchased components are in hand and I finally had some time to put it all together and do an initial vacuum test (without the HV feedthrough).

I was able pump the chamber down to 20 mTorr in about 15 minutes.
Final Vacuum Test Gauge Reading
Final Vacuum Test Gauge Reading
Next up is to mount the HV Feedthough on the empty 6 in blank.
Demo II , mostly assembled, View 1
Demo II , mostly assembled, View 1
Demo II , mostly assembled, View 2
Demo II , mostly assembled, View 2
Ed Meserve
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Richard Hull
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Re: Restarting Efforts on Demo Fusor II

Post by Richard Hull »

Looking fine, Ed. You are virtually there now. All the best on startup.

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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