Search found 60 matches

by Robert Dwyer
Fri Sep 28, 2018 3:05 am
Forum: New User Chat Area
Topic: Budget and Insulator Questions
Replies: 7
Views: 633

Re: Budget and Insulator Questions

If you are on a campus that is doing research that requires vacuum equipment, almost certainly you can find a professor that knows of a storage cabinet that contains spare gauges, flanges, pumps etc... I was AMAZED at what I have found laying around in old storage closets at my university, under pil...
by Robert Dwyer
Tue Jun 12, 2018 2:01 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Atlas of Neutron Capture Cross Sections
Replies: 3
Views: 1336

Atlas of Neutron Capture Cross Sections

Hello All, In my time working with various neutron diagnostics, I came across this very useful tool I thought I would share. https://www-nds.iaea.org/ngatlas2/ This is an Atlas of Neutron capture cross sections vs. energy compiled by those at the IAEA Nuclear Data Center. Be it for fun, or for detec...
by Robert Dwyer
Wed Jun 06, 2018 9:03 pm
Forum: New User Chat Area
Topic: Metal Deuteride Grid Idea
Replies: 1
Views: 806

Re: Metal Deuteride Grid Idea

In reality, most metal grid materials would work. You run into issues of ion bombardment, heating, etc... which effects material thickness and your overall design. Tantalum is a good high temperature material for a fusor. I've used both molybdenum and niobium grids before with no problem. Even Stain...
by Robert Dwyer
Fri Mar 30, 2018 11:24 pm
Forum: New User Chat Area
Topic: TIG welding advice.
Replies: 2
Views: 625

Re: TIG welding advice.

I was first taught to TIG weld by a coworker of mine who had been in the welding industry for years before deciding to pursue and engineering degree. He first had me watch him "stack beads" both with and without filler rod. He then had me do the same on some pieces of scrap stainless steel. Stacking...
by Robert Dwyer
Thu Mar 22, 2018 3:59 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Robert Dwyer Fusor Progress
Replies: 37
Views: 7603

Re: Robert Dwyer Fusor Progress

Hello Everyone, I have not posted in a while and I thought I might make an update on some of the latest news regarding my fusor. First, I did 3 more runs at varying distances (16cm, 12cm, 10cm from source), and found the average output of my device to be 220,000 n/s when running at 50kv at 4.7ma wit...
by Robert Dwyer
Thu Mar 22, 2018 3:31 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Helium-3 Fusor Thread
Replies: 15
Views: 3634

Re: Helium-3 Fusor Thread

Jackson, This sounds like a fun project. The acquisition of He3 would seem to be the hardest, along with obtaining a kilowatt-level power supply to run your fusor and 80kv or higher. You may be able to get lucky and find a university or old radiology lab that may have spare power supplies used in ol...
by Robert Dwyer
Sun Jan 07, 2018 4:18 am
Forum: Vacuum Technology (& FAQs)
Topic: Severe Outgassing Problems
Replies: 7
Views: 919

Re: Severe Outgassing Problems

Never use Isopropyl for vacuum cleaning! It contains lots of water that will embed itself into the chamber walls then outgass during pump down. Acetone is ok, but still has the an issue with leaving films and some some water that may outgass. At my work we primarily use methonal for cleaning vacuum ...
by Robert Dwyer
Sat Jan 06, 2018 11:13 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Robert Dwyer Fusor Progress
Replies: 37
Views: 7603

Re: Robert Dwyer Fusor Progress

I did another run with the fusor today. Pressure: 45 microns Voltage: 47kv Current 4.7mA Data Collection Period: 3 minutes. Dosimeter distance from the center: 18cm Bubbles: 10 I calculated the total isotropic emission rate of 130,288 n/s from the fusor. It is definitely apparent how quickly the neu...
by Robert Dwyer
Sun Dec 31, 2017 9:38 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Robert Dwyer Fusor Progress
Replies: 37
Views: 7603

Re: Robert Dwyer Fusor Progress

I've been doing a few more runs and have found some interesting affects in the fusor. First I noticed that I could get the plasma to light at much mower pressures (10 microns) if I biased the cathode higher, to about 20kv instead of 15kv, before admitting the D2 gas. However, the plasma was wildly u...
by Robert Dwyer
Thu Dec 21, 2017 2:28 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Robert Dwyer Fusor Progress
Replies: 37
Views: 7603

Re: Robert Dwyer Fusor Progress

It has been a few weeks since I last posted. I just finished finals and now that I am winter break, I plan to more with the fusor. I shooting to have an activation setup done by the end of January. First however, I would like to discuss the results I had posted in my my last two posts. I was claimin...