![\"Joe](\"http:\/\/www.contrapositivediary.com\/wp-content\/uploads\/2020\/11\/Joe_Lill_and_10_Inch_Newt___3_8_1970___Cropped.jpg\")
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When I was 14, I took an opportunity and started out on a very<\/em> large project: A friend of mine bought an Edmund Scientific mirror-making kit, decided he didn’t have the time to pursue it, and sold it to me. The kit included a 10″ Pyrex mirror blank, a plate glass tool blank, and all the abrasives needed to grind and polish it. I did most of the grinding in my basement, using a defunct round wringer washer as a grinding station. I followed the instructions in the kit, along with whatever I could find in the library, and though it took a couple of months, in time I had a Pyrex blank with a smooth curve, focusing at about 67 inches. My goal was 70, so I came pretty close, and in truth, 67″ would make for a shorter and somewhat lighter tube.<\/p>\n Now, grinding is only half the job. Polishing the ground mirror surface took sophisticated methods to gauge the accuracy of the curve, which has to be a parabola to focus items at infinity (like stars) to a sharp image. I decided I was over my head, and did the sensible thing: I enrolled in a class at the Adler Planetarium on Chicago’s lakefront, which took up most of the summer that I turned 15. They had an optical shop in the basement that included the required Focault tester, plus a superb teacher, Ken Wolf, who helped me get the polishing done and mirror curve accurate. They were also able to aluminize it, and by that fall, I had a 10″ F6.7 parabolic telescope mirror accurate to 1\/25 wave, which was bogglingly accurate for a first shot by a 15-year-old.<\/p>\n The rest of the scope took another two years and change to complete. A friend’s father made me a tube out of sheet aluminum. I built a tube saddle out of scrap wood and hardware-store aluminum stock. I had no tools more sophisticated than my dad’s circular saw and saber saw. And that was for woodworking–for metal I did it all with a hacksaw and files. I had some help from my high school machine shop teacher, who dug up a piece of iron that he said was hull metal from a scrapped battleship. He cut it to size on the big bandsaw for me. I spent many study hall hours in his shop on one of the lathes, boring out 2″ pipe fittings and making numerous small parts. I owe Mr. Brinkmann a huge debt of gratitude. Without his help and the use of his machines, I could not have finished the scope.<\/p>\n It was going to be a big scope, and a much heavier one than the 8″ Newtonian I had built from a Sam Brown book the summer I turned 14. I turned my attention to building a base. There was a lot of scrap lumber in the crawlspace. I had the notion of building a cement form out of scrap lumber and pouring a solid triangular concrete shape 36″ on a side with bolts embedded in the top for the battleship-metal mount.<\/p>\n So I built me a cement form.<\/p>\n Whoops. Doing some math and library research showed me that the concrete base would weigh at least 400 pounds. Yes, I could make it–but once I made it, I had no idea how I would move it. So I was left with a scrap lumber cement form…<\/p>\n I.D.E.A!<\/p>\n A lot more work and allowance money would go into the telescope before I finished it–more or less–in the fall of 1969. On an early date with a pretty 16-year-old girl I had met in church, I told her about the project and drew a picture of it on her little spiral notebook. (See left. She enjoyed talking about science. So did I. She married me in October 1976, and our flag still flies.)<\/p>\n I used that scope a lot<\/em>, even though it was bulky and heavy and awkward to cart around. In 2000, I (finally!) poured a concrete base for it at our house at the north end of Scottsdale. (See below.) I bought a large plastic trash can to put over the scope to keep the weather off it, and enjoyed it tremendously. Well, we moved to Colorado in 2003. When I went behind the garage to fetch out the now-retired wood base, I discovered that the local termites had been feasting for a couple of years, and there was nothing much left.<\/p>\n I haven’t had the 10″ assembled since. And it’s now about damned time to get to work.<\/p>\n I’ve spent a couple of weekends messing with it. Yesterday I bolted the aluminum tang to the base, and although there will be some refinements, what you see below is pretty much what you’ll see when it’s in service.<\/p>\n![\"FirstDateSketchTelescope](\"http:\/\/www.contrapositivediary.com\/wp-content\/uploads\/2020\/11\/FirstDateSketchTelescope___325_Wide.jpg\")
The form was made entirely from 2″ dimensional lumber, from 2X4s to a scrap of 2X12. I could carry it around with only a little puffing. So I would use the cement form as the telescope base.<\/p>\n![\"10](\"http:\/\/www.contrapositivediary.com\/wp-content\/uploads\/2020\/11\/10_inch_with_Michael_Abrash___2001___500_Wide.jpg\")
<\/p>\n![\"New](\"http:\/\/www.contrapositivediary.com\/wp-content\/uploads\/2020\/11\/New_10_inch_wood_base_1__500_Wide.jpg\")
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