Search found 579 matches

by Dan Tibbets
Fri Feb 17, 2017 1:15 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Neutron Flux Calculation
Replies: 7
Views: 1134

Re: Neutron Flux Calculation

This site is presumably useful. http://www.gammaspectacular.com/fusion_calculator.html Of course the counter, weather bubble or electronic counter needs a calibration. I suppose with some work, you could use silver activation to help calibrate a counter, but the variables- silver purity, etc. introd...
by Dan Tibbets
Sat Jan 07, 2017 3:54 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Variations on Pressure Cooker Fusor
Replies: 2
Views: 898

Variations on Pressure Cooker Fusor

I have in the past made fusor vessels (at least for demo purposes) out of surplus pressure cookers. The first had a single pass through in the bottom of the pan. I have since moved to placing the feedthrough(s) in the lid so that I do not need to reach to the bottom of the pan to work on the feedthr...
by Dan Tibbets
Tue Nov 29, 2016 8:52 pm
Forum: Images du Jour
Topic: Chamber wall rainbows
Replies: 10
Views: 2218

Re: Chamber wall rainbows

Tungsten oxide coating the chamber and electrodes has been a problem for Lawrence Plasma Physics- the dense plasma focus machine. since going to tungsten electrodes, they have been wrestling with this problem for about a year. http://lppfusion.com/experiments-conference-discussions-yield-new-underst...
by Dan Tibbets
Sat Aug 06, 2016 5:20 pm
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Potential,...Energy,... volt,... EV, etc.
Replies: 13
Views: 2608

Re: Potential,...Energy,... volt,... EV, etc.

Dan, It's rather fascinating how little our understanding of a "surface" is, just look up the word surface on wiki: https://en.wikipedia.org/wiki/Surface Very little is known about surfaces, yet our world is entirely made up of surfaces, the floor, the walls the table etc., but when we look into th...
by Dan Tibbets
Wed Aug 03, 2016 10:38 pm
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Potential,...Energy,... volt,... EV, etc.
Replies: 13
Views: 2608

Re: Potential,...Energy,... volt,... EV, etc.

Dan, can you define a surface? You might have a EUREKA moment followed by FACEPALM followed by DOH! A surface (with real surface area greater than 1/ infinity) would be present for any particle or source that was not by definition a point. As I understand Gauss law this is best illistrated by a inf...
by Dan Tibbets
Wed Aug 03, 2016 2:27 am
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Potential,...Energy,... volt,... EV, etc.
Replies: 13
Views: 2608

Re: Potential,...Energy,... volt,... EV, etc.

In the post by S. Sesselman ...... "It makes sense to me at least that we should assign this so called "potential" to the surface of the particle, as the potential obviously falls off at the rate of 1/r^2." Well, that is true for a point source. When the particle has a diameter / surface area much l...
by Dan Tibbets
Wed Feb 03, 2016 6:27 am
Forum: New User Chat Area
Topic: Demo Fusor HV Input (rectifier)
Replies: 14
Views: 3107

Re: Demo Fusor HV Input (rectifier)

I hope you do have a backing pump- a rotary pump that can get down to well below 100 mTorr (100 Microns). A piston pump or venturi pump are not anywhere close to what you need. A diffusion pump does not work well above a few hundred Microns (rule of thumb is 100 Microns) and above 500 Microns the di...
by Dan Tibbets
Tue Jan 19, 2016 6:02 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Spot Welding with a MOT
Replies: 17
Views: 7814

Re: Spot Welding with a MOT

I built a spot welder from a MOT by removing the secondary windings and replacing with about 5 windings of light starter cable wiring. About 3-4 volts and it heated well but not evenly. The major impediment was building a good contact arm structure with, as pointed out, small contact area and abilit...
by Dan Tibbets
Tue Jan 19, 2016 5:47 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: How much gas is a liter, or cubic foot?
Replies: 5
Views: 1861

Re: How much gas is a liter, or cubic foot?

Note that the above numbers is for dry air. The water content is often ignored, though it is significant. The percentage of air that is made up of water vapor may exceed ~ several percent by weight, or is that volume? My recollection is that the partial pressure of water in expired air from humans i...
by Dan Tibbets
Sun Nov 15, 2015 9:46 pm
Forum: Fusion --- Past, Present, and Future
Topic: Tri-Alpha Energy just launched its website
Replies: 21
Views: 6009

Re: Tri-Alpha Energy just launched its website

Perhaps exposing my ignorance again, but method and efficiency of heating is certainly important, but the dominate consideration is confinement. If particle and KE confinement is not adequate, even a tremendously efficient heating mechanism is useless. I've not been impressed with the temperatures t...