We welcome hobbyists, educators and the scientifically
adventurous to the fascinating world of vacuum technology

Ever dreamed about building an x-ray tube? Or coating your own telescope mirror? Maybe even constructing an electron microscope? Perhaps you are a high school science teacher who would like to introduce simple yet interesting electron, ion and plasma physics experiments and demonstrations into your classroom. People the world over are involved in projects like these and the common thread is the use of vacuum technology. This site represents a key resource for you to join this network of hobbyists, students and educators.

The May 2020 issue of the Bell Jar is available

This sixth issue may be found on the Articles & Publications page. Topics include an update on the use of refrigeration service vacuum pumps, Mark Atherton on his single supply thermocouple vacuum gauge controller and articles of possible interest in Vacuum Technology & Coating magazine.

Introducing the BVES

March 25, 2020. Complete documentation for a low-cost vacuum educational tool (the Basic Vacuum Education System or BVES) is now available. Check out the Vacuum Education page for details.

We're (still) Rebuilding!

March 20, 2020 Status Summary:

Over the past few months, the big news has been the resumption of the Bell Jar as a monthly, free publication. I have gotten good feedback but it will probably take a while to start receiving reader projects. Hopefully that will come.

In August 2019 a new Education section was added (see the navigation button). This set of pages contains a set of information on vacuum training equipment (including legacy systems), details on construction, exercise information, etc. Information on new trainers is in progress.

During the latter half of 2019 the old Flash videos were updated. The Forum is now disabled and a number of pages have been retired. Some are simply not relevant anymore. Others need to be retooled. This would include the Books page where I had Amazon links. This will be replaced with descriptions and no links.

I am no longer providing accessories such as adapters, chambers, etc. The volume was never high enough to justify the effort. These will be replaced by drawings and commercial sources.

I stopped posting links to my Vacuum Technology & Coating articles in 2012. The publisher also changed the the on line magazine server. I will have an index to articles (2009-present) with issue month/year, title and an optional brief description. As a precursor to this, I have been grouping my articles into topic areas (gauging, pumping performance, etc.) and publishing a selection in each issue of the Bell Jar.

I have retained my "man-in-vacuum" logo, even though it creeps some people out (so I've heard).


Modern atomic physics is the child of the vacuum pump.

Karl K. Darrow, Electrical Phenomena in Gases, Williams & Wilkins Co., Baltimore, 1932


Copyright © 1992-2020 Stephen P. Hansen