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A Short History of Amateur Telescope Making
by Frank Ward



November 1925 is considered by most of to be the birthday of Amateur Telescope Making. Before that date there were small groups of hard working experimenters and technically minded individuals in several countries. But in November 1925 Scientific American magazine ran an article describing a group led by Russell W. Porter that worked nights and weekends in a small building near Springfield, VT.

That article started a landslide of interest filled letters to SA and soon more articles were included in their monthly publications. Then came some wonderful books. Men and women described in their own words what they had done....using plate glass and optical glass.( Pyrex, that low expansion glass we love so much wasn't invented until the early thirties.) Illustrations from that period show the basic tester we use but with a kerosene lantern for a light.

The Rev. William F. A. Ellison, Director of the Armagh Observatory at the time Wrote a how-to book for amateurs...Imagine that! The only comparison today would be if a director at NASA took the time to write a book on making model rockets. To pass on his knowledge freely and helpfully established that attitude among all ATMs. It became the cornerstone. You were helped, help another.

In 1935 the first of three books which collected Scientific American articles was published. We refer to them as ATM I, II, III. During the thirties these books led many an inquisitive mind to grind, polish, figure and mount a telescope mirror. The standard then was six inches in diameter and had a focal length of 48 inches. A very modest mirror by today's standards when 20 inch mirrors are commonplace and advanced amateurs are creating 40-inch mirrors and planning larger.

We in the United States are very fortunate that ATMs had developed to the level of competence they had at the outbreak of World War II. It gave our war effort the needed optical specialists used to manufacture thousands of different magnifying and sighting devices. For many years after the end of hostilities there were surplus optics available through auction and purchase. This gained new, peaceful, life in the hands of the world's ATMs. Bomb sights became telescopes and wing cameras began photographing comets and meteors. Remember, the ATM loves making the equipment astronomers use. They aren't always as interested in searching the skies.

The Space Race of the 60's led to manufacturing improvements and techniques that filtered down to the amateurs. It was rare by then for an ATM to silver the surface of his hand made mirror. Aluminizing became the standard, leading to aluminizing and protective coatings, then the addition of special layers of chemicals that filtered out stray light leaving only special colors became available. Then in 1970 the BIG jump came. A gentle monk in California looked through a telescope and said, "Everyone in the world should be able to see this." That comment led to his invention of a method of mounting large telescopes. It is called the Dobsonian mounting in his honor (or DOB for short) Until his hands cut wood and fashioned Formica and Teflon the worlds major and minor telescopes mostly revolved on metal bearings and machined parts. They sometimes took years to make. His plans allowed amateurs to fashion a mounting made of wood and cardboard tubing that efficiently supported the mirror and allowed it to show the glories of the skies to thousands. In San Francisco ATM's took their new DOB's into the streets at night and offered the sights of the night sky to anyone walking by. They had been helped, they wanted to help others.

We have closed the book on that century and begun another. I hope you won't snap the cover shut without trying your hand at creating that most intricate and delicate instrument the Telescope. You can build one, you know, with only hand tools a little wood and a lot of friends who consider it a privilege to assist you. How do you start' By pushing the links on these pages...as you do your whole world will expand...out to the stars.