From HANSEN35@delphi.comSun Jan 7 08:23:55 1996 Date: Sat, 06 Jan 1996 21:55:25 -0500 (EST) From: HANSEN35@delphi.com To: derrick.mancini@fysik.uu.se, cgek@cc.newcastle.edu.au, 74071.1155@compuserve.com, epv%pcsimail@pcsi.cirrus.com, edharris@mps.ohio-state.edu, kintruj@uni-muenster.de, tron!weso.dnet!odhner@uunet.uu.net, tony_smith@mbnet.mb.ca, dave=sharp%legal%corp=hou@bangate.comaq.com, collierb@mcmail.cis.mcmaster.ca, khamar@mailhost.tcs.tulane.edu, shill@maui.com, mmeyer02@interserv.com, filchock@cup.edu, kauffman@vnet.ibm.com, tomj@wps.com, covent@innet.be, kukkonen@snakemail.hut.fi, mitton@mail.ip.portal.com, sdl@harare.iafrica.com, billbeskimo.com Subject: Vacuum Newsletter #5 ************************************************************************** * ----------------------------------- ----------------- * * the Bell Jar (electronic version) #5 (January 1996) * * ----------------------------------- ----------------- * * * * This newsletter contains material which has been extracted from the * * hard-copy newsletter of the same name. Devoted to the vacuum * * experimenter, the intent of "the Bell Jar" is to broaden interest * * in vacuum technology through useful discussions of theory and * * technique, and to present ways in which a variety of apparatus may * * be assembled using common and inexpensive materials. Information * * on "the Bell Jar" may be obtained by sending email to the editor, * * Steve Hansen, at hansen35@delphi.com or by writing to 35 Windsor Dr., * * Amherst, NH 03031. Please feel free to circulate this electronic * * version, intact, to others who might be interested in the subject * * matter. New numbers will be mailed at approx. quarterly intervals. * * Email subscriptions are free and may be obtained by contacting the * * editor. Comments, contributions and criticisms are always welcome. * * Copyright 1996, Stephen P. Hansen. * ************************************************************************** In this issue: Some Recollections (Franklin Lee) What's in the current issue of "the Bell Jar" (Print Version) *********************** For a number of us, Frank Lee's contributions to Scientific American's Amateur Scientist column were what sparked our interests in vacuum technology. Certainly, in my case, this teacher and advocate of hands-on science was a major factor in my life's interests. Frank recently commented that he felt that he never lived up to his potential, that he could have been another Edison. Well, perhaps the world didn't need another Edison. The inspiration that Frank provided to others to do science, in my opinion, is of similar value, albeit harder to recognize and measure. The following material has been pieced together from several correspondences with Frank that occurred between late-1994 and mid-1995. This was before Scientific American revived The Amateur Scientist as a regular feature. - Ed. Some Recollections Franklin Lee I was born in a small town, Granite Falls, Minnesota, population 1500. For some reason that town was the home of a number of talented or famous people. There was Doctor Wellcome, one of the founders of Burroughs Wellcome Drug Company in England. There was Olai Lende, the inventor of many automobile components such as the differential, screw drive steering wheel, etc. Presidential candidate Hubert Humphrey's father had a drug store in Granite Falls before moving to No. Dakota. Senator Volsted lived across the street from Grandma Lee and Archibald Bush, a founder of 3M Company, came from Granite Falls. His charitable gifts exceeded $1 billion with $5 million a year going to Granite Falls for the schools, etc. Then there was Mildred Lee, my mother, first woman admitted to the Minnesota Bar, recognized poet and historian, and an early feminist. My first attempt to use vacuum occurred in 1934 or 35. I was trying to make an electronic tube as my allowance was not enough to purchase a ready-made tube. I was 13 at the time and didn'trealize what high vacuum was. I tried a water aspirator which got me to 30 mm Hg, the vapor pressure of water. What I got was a Geissler tube with blue light. This ended my childhood involvement with vacuum. My last year in high school was rather turbulent. I was 15 at the time and running in all directions. I was making fireworks contrary to my parent's views. For a dollar, one could get 5 lbs. of sodium chlorate at the hardware store. It was used as a weedkiller. When mixed with charcoal or other combustible material it was a nice explosive. With a friend or two, I went outside town and blew up tin cans, split logs, etc. It could also be used to make colored flares. I also made a small cannon out of two pieces of steel pipe - 3/4" for the barrel which was placed within a piece of 1" that served as reinforcement. I would pack the barrel with 2" of "mix", put in a wad of cloth and insert a 3/4" glass marble as the projectile. The marble would go through 2-1/4" of pine. Once it missed the boards and went through one wall of a shed and out the other. I did have the sense to stand behind the cannon while loading it. Once while loading it, the cannon went off and took one finger and messed up my hand. Dad made me clean house. This occurred again when I was caught bringing tear gas to school. A more constructive endeavor was the analytical balance I made at about this time. The fulcrums were razor blades, the weights were nickels (about 5 gms), short lengths of rolled-up wire (1/10 to 2 gms) and pieces of foil (1 to 50 mg). I got interested in electronics at about this time. The next project that involved vacuum was when I became employed by Union Carbide in the research department. This was around 1943. The project involved some work with a vacuum furnaces. The furnace consisted of a 1-inch diameter ceramic tube with a boat of high carbon ferrochrome, chromium oxide and calcium silicate flux. The idea was to get the carbon in the ferrichrome to react with the oxygen in the chromium oxide. The vacuum atmosphere was to improve the equilibrium. While the project resulted in a production process, it was soon displaced by a better method. It wasn't until rotary compressors became commonplace that I realized there could be an opportunity for an amateur system. When I started teaching chemistry at Erie Community College in 1953 I had lots of opportunity to make apparatus for the school lab. One item was a molecular still which would fractionate mixtures like vegetable oil at temperatures low enough to avoid decomposition. I didn't spend much time on this as it was sort of dull. When C.L. Stong took over the Amateur Scientist column he suggested an article on a particle accelerator. I don't know how he got the idea, although Albert Ingalls, the previous editor of the column, had produced an article on an amateur-built cyclotron. This used commercial vacuum apparatus. Trying to make due with something simpler, I got a lot of used refrigeration compressors and tried them out. A local glassblower made me a McLeod Gauge (based on information in "Review of Scientific Instruments" - there are lots of interesting articles in that journal). The high vacuum mercury diffusion pump was also based on material from "Review of Scientific Instruments." The resulting article, "A Homemade Atom Smasher," was published in May of 1957. The machine consisted of a 350 kV van de Graaff electrostatic generator with an accelerating column that would produce a beam of electrons. Later in 1957 I started supplying Van de Graaff terminals to hobbyists who had read my article in Scientific American and one thing led to another. After the accelerator article came out I was ready for requests for information and supplies. My wife did not take kindly to my hobby as it cluttered up the cellar, drew on my time and involved a lot of mail and phone calls. My friend Morris Most had a sewing machine company that was not doing well and he was willing to share my responsibilities. He took care of the mail, bookkeeping and shipping & receiving. I recognized a need for science education equipment and started adding this to the line. There was a big market then and I went after what Science Kit wanted but couldn't get from the other suppliers. This piece of the business soon eclipsed the amateur market which remained more of a hobby than an enterprise. When it came to having a turret lathe, punch press, two drill presses and seven assistants in the cellar two nights a week my wife again suggested that I clear it out. By 1975 Morris and Lee had a part time crew of 10 and a turn-over of about $1M in current dollars. Morris died in 1977 and I quit teaching to take over. The business was a mess by this time and it took some 2 years to get back to profitability. In 1984 my older daughter and her husband took the plunge and came into the business. Ray and Nancy proceeded to cull out all the products of marginal profit and reduced the product line from about 200 items to about 50. The company changed its name in 1992 to Science First and is fairly sound with only 12 employees and a $1M turnover. Competition is coming mainly from the Far East and I see a real challenge ahead. Fortunately we have a large investment in high tech tooling which, for now, allows us to compete. Returning to the amateur products, the Morris and Lee customers were a mixed lot. Some were experimenting with gravity devices - I tried to talk them out of making purchases. Some were very talented with lots of money to spend. One ambitious project was a full scale particle accelerator that must have cost $5000 to build. All were people who wanted to see things happen. All of the amateur business was dropped in 1984. I did continue to sell the 500,000 volt Van de Graaff kit but stopped advertising around 1990 and I only sell 5 or 6 a year by word of mouth. We do sell 200,000 and 500,000 volt generators through dealers like Edmund Scientific and some hobby shops. Scientific American pretty much dropped the Amateur Scientist column around 1973 after Stong died. Virtually all the amateur business I had came from his articles since he had included my name and address. I later made gas chromatographs, electronic balances, spectrophotometers, air liquifiers, etc. but just for my own entertainment. One of the big differences today is a lack of supplies. Fear of litigation has made suppliers unwilling to deal with amateurs. The fear of law suits has also diverted some nice stuff away from people into the dump. Its simply hard to buy something that you could possibly get hurt on. Surplus dealers are one remaining good resource - they get the original supplier off the hook to some degree. Scientific American once published an article on making amateur rockets using zinc powder and sulfur as fuel. I think they got chewed out by some group for that one. Also, we have become a nation of button pushers. I feel that one reason for a lack of interest in such projects is the availability of computers - many people prefer pushing buttons to using tools. (Certainly, the Morris and Lee kits required a good degree of competence on the part of the purchaser to put something together that worked. It took me a couple or three years to really get my Hickman diffusion pump to actually do something...but I learned a lot in the process. There seem to be fewer people now who are willing to really work to make a project go, but they are there and they seem to feel like the group that business forgot. If they didn't exist, `the Bell Jar' would have no readership. - Ed.) *********************** WHAT'S CURRENT IN "THE BELL JAR" (PRINT VERSION) In addition to the above, the Summer and Autumn 1995 issues of "tBJ" contained articles on the following topics: * Update on Chris Frye's transmission electron microscope * Solder glass bibliography * Backstreaming from oil-sealed mechanical pumps * Replicas of antique cold-cathode tubes * Evolution of the x-ray tube * Some simple vacuum hardware for classroom use * Demonstrate an electron microscope (easy and cheap) * Introductory vacuum experiments * Atmospheric pressure plasmas *tBJ*