It seems like creating a vacuum should be a pretty easy job, but it turns out that sucking all the air out of something is harder than it seems. A cheap vacuum pump will get you part of the way there, but to really pull a hard vacuum, you need an oil diffusion pump that costs multiple tens of thousands of dollars.
Or, you need a bunch of thrift store junk, a TIG welder, and a can of WD-40. At least that’s what [Lucas] put into his homebrew oil diffusion pump. The idea of such a contraption is to vaporize oil in a chamber such that the oil droplets entrain any remaining gas molecules toward an exhaust port. His low-budget realization of this principle involved a lot of thrift store stainless steel cookware, welded together with varying degrees of success, with liberal applications of epoxy to seal up any leaks. And an electric smores cooker for the heating element, which was a nice touch. The low-budget approach extended even to the oil for the pump; rather than shelling out for expensive specialty oil, [Lucas] distilled some from a WD-40 silicone spray lubricant.
The video below details all the travails [Lucas] encountered along the way, plus the testing process. The results were at least encouraging — the diffusion pump was pulling vacuum far in excess of what the roughing pump was capable of. He clearly still has some work to do, but getting as far as he did with the scrap heap of parts he cobbled together is pretty impressive.
[Lucas]’ goal with all this? A fusion reactor. No, not that kind. This kind. Continue reading “An Oil Diffusion Vacuum Pump From Thrift Store Junk”
Do you remember in 1989 when two chemists announced they’d created a setup that created nuclear fusion at room temperature? Everyone was excited, but it eventually turned out to be very suspect. It wasn’t clear how they detected that fusion occurred and only a few of the many people who tried to replicate the experiment claimed success and they later retracted their reports. Since then, mentioning cold fusion is right up there with perpetual motion. Work does continue though, and NASA recently published several papers on lattice confinement fusion which is definitely not called cold fusion, although it sounds like it to us.
The idea of trapping atoms inside a metallic crystal lattice isn’t new, dating back to the 1920s. It sounds as though the NASA method uses erbium packed with deuterium. Photons cause some of the deuterium to fuse. Unlike earlier attempts, this method produces detectable neutron emissions characteristic of fusion.
Continue reading “NASA Claims Cold Fusion Without Naming It”
Nuclear fusion, as a method of power generation, continues to elude humanity. It promises cheap, virtually limitless energy, if only we could find a way to achieve it. On the other hand, achieving nuclear fusion of a few atoms just for the fun of it is actually quite doable, even in the home lab. [Jackson Oswalt] is one of the youngest to pull it off, having built a working fusor at home at the age of 12.
The fusor consists of a cross-shaped chamber, which is pumped down to a high vacuum to enable the fusion reaction to occur. Deuterium is then pumped into the chamber, and confined by an applied electric field from a power supply in the vicinity of 50 kV. With the right combination of geometry, vacuum and other factors, it’s possible to fuse atoms and observe the characteristic glow of the reaction taking place.
In order to be recognised as having achieved fusion by the Open Source Fusor Research Consortium, one must typically have proof of the release of neutrons from the fusion reaction. [Jackson] showed this with a neutron detector setup, by inserting and removing it during a run to demonstrate the fusor was the source of the signal. Photos of the glowing fusor don’t go astray, either, and [Jackson] was more than happy to deliver.
We’ve seen fusor builds before – [Erik]’s build got him into the Plasma Club back in 2016.
[via Fox News]
By far the coolest projects we see are those dealing with high voltages and deep vacuums. Vacuum tubes of all types fall into this category, as do the electron microscopes we see from time to time. The king of all vacuum and electron hacks is the Farnsworth Fusor, a machine that will both transmute the elements and bathe you in neutrons. Fun stuff, and [Daniel] has a great tutorial for building your own.
[Dan]’s fusor is surprisingly simple to make. Obviously, the most important part is the vacuum chamber which in this build is based around a glass oil cup cylinder. With just a few roughly machined parts – the only tool needed to make the metal plates is a drill press – it can hold a low enough vacuum to contain a star in a jar.
For reasons of safety and sanity, [Dan] isn’t running his fusor at a high enough voltage to actually fuse deuterium into helium. This is really just a beautiful, glowey demonstration of what can be done with enough knowledge, the skills, and a handful of parts.
The magnum opus of alchemy was the Philosopher’s stone, a substance that was able to turn common metals into gold. Unlike alchemists, [Carl Willis] might not be poisoning himself in a multitude of ways, but he did build a Farnsworth fusor that’s capable of turning Hydrogen into Helium.
To fuse Hydrogen in his device, [Carl] first evacuates a vacuum chamber. Deuterium (Hydrogen with an added neutron) is injected into the chamber, and a spherical cathode made of Tungsten is charged to 75 kV. The deuterium gas is heated and confined by the cathode and fuses into Helium. The electrostatic confinement of the plasma isn’t very much different from some old CRT tubes. This isn’t a coincidence – both the fusor and CRTs were invented by the same man.
While no fusion experiments – including some billion dollar experiments – have ever produced a net energy gain, this doesn’t mean it’s not an impressive engineering feat. If you’d like to try your hand at building your own fusor, drop by the surprisingly active research forum. There’s a lot of really good projects to look through over there.
[Will Jack] built a heavy water fusion reactor and then won district and regional science fair projects with it. Someone give this man a job!
We looked in on his fusion reactor about a year ago. At the time he had managed to build a magnetic containment field but didn’t have the voltages or the deuterium necessary to achieve fusion. We’ll that’s all changed. Using a boron-10 lined sensor tube he’s managed to detect the rise in neutron counts that would indicate fusion. Remarkable. He’s now working on a refined gas system that will allow him to increase the deuterium purity by cutting down on the leak rate. He mentions a few other hardware improvements such as a new containment unit and an ion source upgrade. Both of these concepts go beyond our knowledge so do make sure to put on your Nuclear Engineering hat while reading through his project update.
Do you ever wonder what projects your neighbors have going on in their basements? [Will Jack’s] neighbors might be surprised to find he’s building a fusion reactor. The first step toward completing a Farsworth-Hirsch Fusor is up and running. The picture above shows heated plasma contained in a magnetic field. Next he just needs to up the voltage and inject some deuterium.
Yeah right! Deuterium, aka heavy water, is extremely rare and very difficult to refine. If you’re not familiar with the substance, you should get your hands on the NOVA episode: Hitler’s Sunken Secrets.
We’re glad to see that [Will Jack] is donning a lead vest for protections. [Will O’Brien] cautioned us about the stray X-rays these things produce when he covered fusors back in 2007.