Sunday, September 14, 2008

 

The 37-Year-Old Telescope


Some Amateur Telescope Making projects are like fine wine. Set them aside for a while, let them mature, and they become sweet. Others? More like Boone’s Farm, muchachos. Let ‘em sit too long and they turn to vinegar. The question facing ol’ Unk was which category would the 37-year-old mirror fit into? I was finally, with the help of my ATM-friend, Pat Rochford, determined to find out.

What kind of jibber-jabber is your silly ol’ Uncle spouting now? As always, it’s best to start at the beginning, and this beginning began a right smart while back. Let’s set the WABAC Machine for the summer of 1971...

For those of you who weren’t around for that halcyon year, the sixties had rolled over to the seventies the previous annum, but 1971 had more to do with the previous decade than with what was to follow. When I think about what we listened to and watched that year, I feel old, real old.

Naturally, music was in the air. The big news (for us silly kids, anyhow)? Former Beatle George Harrison’s Concert for Bangladesh. The surprise hit album? One that amazed and scandalized in those simpler times, Love it to Death by a dude calling himself Alice Cooper. Not quite your cup o’ tea? Gordon Lightfoot had a big hit with “If You Could Read My Mind.” Movie-wise we chose from flicks as diverse as Carnal Knowledge (real good) and Fiddler on the Roof (purty much the last victorious gasp of the traditional filmed musical). What were we watching on TV on the three channels that were all we had down in the Swamp? All in the Family and The Flip Wilson Show. Political news? Watergate was aborning but not with us yet. George McGovern was cranking up his ill-fated campaign, though. In science, Apollo 15 trumped everything else, naturally.

Like I said, long, long time ago. Sigh. Seems that way sometimes, too, though if I really concentrate I can still hear the faint sound of a sitar way off in the distance. What was your old Unk doing at the time? Purty much what I do now, obsessing about amateur astronomy. One thing was different, however. This may shock y’all, but back then, Unk, who is probably best known today as an ATB (Amateur Telescope Buyer), was an honest to god ATM, going so far as to grind, polish, and figure several Newtonian primaries.

I will admit that even then I was more interested in looking than making, so what got me involved in the grit n’ glass game? One thing: poverty. As I’ve mentioned a time or two, my prime instrument for the longest time was a Palomar Junior, a used 4.25-inch Newtonian from Edmund Scientific that I’d somehow been able to glom onto in 1966. While I loved that scope (make that “love;” she still occupies a hallowed spot in Chaos Manor South’s Massive Equipment Vault), I was becoming less and less satisfied with her.

Why? Hard as it may be to believe, by the late 1960s – early 1970s light pollution was already beginning to spread with a vengeance in suburban America. Back in the mid 60s, the skies in Mama and Daddy's subdivision were hardly pristine, but the Milky Way was at least faintly visible on most Moonless nights, even those humid (cut it with a knife) Possum Swamp summer eves. Given that humidity, the Milky Way’s presence meant the area was still quite dark. The first change for the worse came with the building of the local shopping mall in 1967. The (for the time) gargantuan Bel-Air Mall with its acres of parking lots didn’t do too much to brighten my sky, but it soon attracted numerous hangers on—car lots and strip malls—that danged sure did.

Not only that: by the end of the 1960s the city began to catch up on streetlight installation. Until then, suburban mercury vapor lights had been fairly few and far between. Then, all of a sudden, there was one on the power pole in front of our house. The vacant lot next door where me and my buddies in our Backyard Astronomy Society held our star parties? Sadly, a house was built on it at about this time; luckily, it was bought by an understanding couple who turned off their porch light whenever they noticed me and my Pal were out and about.

Alas, this understanding and friendly couple moved away after a while, and next door was then occupied by decidedly peculiar and mean-tempered folks (the husband was a drunk and an absolute nutcase and the wife was just plain weird) who immediately decided they needed a couple of huge mercury vapor yard lights—probably in part to keep an eye on what that weirdo neighbor boy was up to at all hours of the night. By 1968, my poor Pal Junior was losing ground, showing DSOs not much better than what my first scope, a 3-inch Tasco Newtonian, had done.

Not that I hadn’t felt the stirrings of aperture fever before this time. From the backyard in the Pal Junior M13 was a (bright) smudge. What to do? Get a 6-inch, that standard of ADVANCED AMATEURS back then. B-U-T. The Edmund Space Conqueror and Criterion RV-6 Dynascope both hovered at 200 bucks, a seemingly insurmountable obstacle. Why, then, I’d follow in the footsteps of Russell W. Porter and my other amateur astronomy heroes and roll my own. Surely Sam Brown wouldn’t let me down? A mirror kit and a copy of his All About Telescopes and I’d soon be glob busting.

Lucky for naïve little me, one of my buddies and his dad had done a 6-inch mirror and they offered to show me the ropes. I doubt I would have gotten the project even an inch or two off the ground without their aid. With their patient instruction, though? Mirror making turned out not to be as tough as I’d feared. As I proceeded, I even managed to get The Old Man (OM) involved in the project—making a Foucault tester was just the sort of project he enjoyed.

I zinged along, not making too many mistakes. Oh, I had to back-up a grade or two of grit a time or two, learning in the process the valuable lesson that cleanliness really is next to Godliness—when it comes to making mirrors, anyway. Finally, on one pretty spring day it appeared I was done. I had managed to keep the focal ratio at right around f/8 or a wee bit more. Yeah, there was, I thought, still some of the dratted and dreaded turned-down-edge I’d struggled with, but I was convinced I was in “good enough” territory.

I’d originally planned on using vile chemicals to silver the mirror myself, but the Old Man put his foot down about that. He (to my amazement) offered to pony-up the simoleons required for aluminizing. Part of the reason was no doubt his natural generosity. The other part was, I suspect, his understandable reluctance to allow the frightening combination of his often-careless 14-year-old son and a batch of poisonous chemicals.

I also believe he had been bitten just a little bit by the amateur astronomy bug and wanted to give my little project the best possible chance of succeeding. Ham radio was his passion; he was a real Old Timer—W4SLJ, now a Silent Key—but some of my love for the night sky must have rubbed off in the course of those many evenings when I’d burst into the family room demanding he come out and look at the latest wonder I’d discovered with my 3-inch Tasco.

After a seemingly interminable spell, the mirror was back. The intervening weeks had not gone to waste, however, with me spending the time assembling something that resembled a tube (stovepipe) and a focuser (plumbing parts), and  a "pipe mount," a German equatorial made of, yes, pipes. I did my best to get the RA and declination motions just as smooth as I could. Oh, the mess I made with valve grinding compound in the course of "lapping" the pipe threads. I thought Mama was gonna blow a gasket when I walked into the den in my good school clothes, which were now generously adorned with nasty black streaks and splotches.

I also needed a spider, a secondary holder, a secondary mirror, and a main mirror cell. I was truly astounded when the OM sprung for a secondary. The spider, secondary holder, and primary cell were a testament to Daddy’s metal-working skills, acquired in the course of many years of home-brewing his rigs (ham radios).

Frankly, the resulting tube and mount didn't look half bad, and I began to imagine actually using the scope on the sky. Nevertheless, I was scared. The OM seemed to have confidence in me, frequently asking what I’d use for my First Light object, but I wasn’t so sure. In fact, I was doubtful what I’d made would be much better than a shaving mirror.

First Light Night came and I braced for disappointment. Daddy and I hauled the whole business out into the backyard. This felt like a serous scope, at least. I hesitated, but the Old Man prompted, “Go on now.” I pressed my eye to the eyepiece of the finder we’d cobbled together (a couple of pieces of aluminum tubing, an old Wollensak camera lens, and a homebrew crosshair eyepiece). Homed-in on Saturn. I hesitated, “You look first Daddy.” He would have none of it. So, in went my 12mm Ramsden and to the eyepiece went my hopeful but wary young eye. Blob. Big blob.

I moved the focuser in and then out and, shoot, THERE SHE WAS! We were maybe two years past a ring plane crossing, so Saturn’s wondrous halo was nicely displayed. The planet was sharp, impressively sharp, with the Cassini division obvious almost all the way around. How did it compare to the Pal Junior? Brighter. Sharper, too, I thought. And what were those little dit-dots? Moons. In the Pal I could usually just make out Titan, but in my new 6-inch, three more were immediately obvious.

I pointed the new scope, my new scope, built by me, at many more objects on this storied night. I gave the OM plenty of eyepiece time, and he accommodated me by sticking with it for an hour or so before allowing that he reckoned he’d head on in to watch his show—probably Mission Impossible, which was his favorite that year. I, he thought, should press on. I did indeed keep it up well into the wee hours, until the carport light eventually flashed on and Mama appeared at the backdoor with her oft-recited “It is two o’clock in the a.m., young man, you get yourself inside.”

Naturally, I was purty pumped following my First Light success, and the months that followed saw quite a few incremental improvements to the 6: a real tube and a real rack-and-pinion focuser. I believe we got both from A. Jaegers of Lynbrook, NY, the same place I’d got the mirror making kit. Back in the Long Ago, Jaegers was almost up there with Edmund Scientific as the go-to guys for poverty stricken amateur astronomers.

Even before the improvements there was no doubt the scope performed well. M13 was a treat compared to what I’d seen in the 3-inch and 4 ¼-inch scopes. On good nights, it finally looked like a big ball of stars. And yet…and yet. Somehow it all seemed too easy. Surely I had no talent for this. What success I had was likely due to the help of my friend’s daddy, my Old Man, and Sam Brown. The images looked good, but I had a sneaking suspicion I had fouled-up. In my mind, the dimensions of that turned-down-edge grew and grew, despite the evidence my eye provided. My “flawed” 6-inch ate away at me, and I determined I’d do a new mirror, another 6-inch f/8, and I’d do it right this time.

When Mama asked me what I wanted for my birthday the following summer, I unhesitatingly chirped, “A 6-inch mirror kit from Jaegers; it’s only $12.95.” I had secretly wanted to ask for the step-up kit, which provided a blank with a pre-generated f/8 curve, but I thought $14.95 was probably more than the traffic would bear. Mama assented, though she was more puzzled than ever that I didn't want a slot-car like the boy next door, and that I was going to make yet another telescope—I already had two. How naïve the poor woman was to the ways of the astronomy equipment junkie! Actually, I didn't plan on a whole ‘nother scope, all I wanted to do was replace the mirror with one that was More Better Gooder.

In retrospect, it’s possible I was right. My first mirror was fine, but I could do better. I’d done more reading at the library and in Sky and Telescope and felt better equipped to handle the task. I exercised more care this time, too, especially regarding cleanliness. I also did my dangdest to keep that consarned edge under control, addressing that problem just as soon as it reared its ugly head. I also developed the idea that the most important part of the process is putting a good polish on the mirror. I don’t know how true that is, but it stood me in good stead. The end result after a couple of months of slow and steady work was a mirror—and a telescope—I was finally proud of.

There things stood till after my high school graduation in 1971 when I got bored. I had just graduated from high school, been accepted at a university, and in the wake of that excitement felt downright let-down. What to do? How about another scope? What kind of scope? The natural thing would have been an 8-incher, but the idea of doing a larger primary made me uneasy. Hell, even on the second six-inch I’d still felt like I’d been flying by the seat of my pants. Also, the cost of an 8-inch kit, about 20 bucks, was a bit rich for my taste—I now had to pay for gas for my 1962 Ford Galaxie (natch), you see. Doing an 8 would also have meant a new tube, a new spider, and maybe a new secondary and secondary holder..

Instead, I decided I’d do another 6-inch and reuse the current OTA, just cutting it down. Cutting it down? Yep, I’d decided I’d take on a challenge for 6-inch Newt number three, a FAST f/6 mirror. All the books on ATMing warned about how hard it was to do “high-speed” optics, and all advised beginners to stick with f/8. Well, hell, I wasn’t a beginner any more, was I? Where would I get the money for another Jaegers kit? I’d just ask for a combined birthday and graduation present package: the portable 8-track tape player I’d had my eye on and the kit (although I probably had enough abrasives left from the previous two outings to do another mirror). Mama didn't say a word as she wrote yet another check to Jaegers; she’d learned to humor her crazy son.

For some reason, my new kit arrived much sooner than the other two had, and I set about hogging out the deep(er) curve, working with a will as Bob Dylan’s Greatest Hits Volume II played on the 8-track. Before long I was polishing. As was my custom, I tried to do as good a job with that as was humanly possible, and prob’ly spent way too long in that endeavor.

I was just getting to the point where I figgered it might be time to try to do that dreaded f/6 parabola when the phone rang. Mama stuck her head out the door and announced it was one of my “crazy theatre friends.” "Crazy," yeah, but I could see Mama was actually pleased. My brother had been doing local theatre since he was the weest of wee sprouts, and Mama had enjoyed playing Stage Mother for years. To her, theatre was considerably more normal than young Unk's usual pursuits—amateur astronomy and comic book collecting.

I’d developed my interest in community theatre not because I had over-much talent, but because it was a great place to hang out, and most of all, a great place to MEET CHICKS. Seeing as how I’d had some minor success in that area, I was only too happy to pitch-in and help with set-construction on a production of The King and I. I continued work on the mirror in fits and starts, but the sessions became less and less frequent.

Finished mirror or no finished mirror, I was having a great time over the course of what turned into my best summer vacation ever. I hadn’t lost interest in observing or in completing my primary, but in June I began dating a fascinating and lovely young woman, Linda, who I'd met at another community theatre where I hung out, and she began to eclipse the Sun, Moon and stars for me. Anyhow, as September came in it was time to forget grit and glass and head off to college. I was a little sad that I hadn’t quite finished the f/6, and resolved I’d just shelve it temporarily, finishing her up during Christmas vacation.

When Christmas vacation came, though, there was the holiday to enjoy with the first love of my life. I didn't touch the mirror the whole time, and one day it migrated from the top of my dresser to a cardboard box in the closet in my old room. There it stayed while Miss Linda and I married, sadly, got divorced (my fault, to my ever-lasting shame), I continued college, did a tour of duty in the Air Force, unwisely got  remarried, started a career, wisely divorced, and finally got hitched to Miss Dorothy (one of the FEW things this old boy EVER got right). Until…

One afternoon my best friend and observing buddy, Pat, stopped by good old Chaos Manor South to drink java and shoot the breeze about the current state of amateur astronomy as is our wont. That wasn’t all he came by for, though. Unlike me, Pat, despite a long amateur astronomy career, did not get bitten by the mirror making bug as a youth, but in middle age, and had been bitten hard.

He’d brought his current project, a 6-inch, by so he could get my opinion about its Foucault test appearance. After we’d taken a look at it, one of my few remaining neurons fired. “Hold on Pat; I’ve got something to show you.” I ran upstairs, rummaged around, and recovered the box containing the f/6 primary. It had been sitting around at Chaos Manor South for the last couple of years, since we'd sold the old family home after Mama went to her reward. The mirror almost went into the trash pile then, but I had the sense to look in the vaguely familiar box first, and there it was almost four decades later, a little yellowed, but unblemished.

Pat and I slammed it into the Focault rig he had brought with him. After squinting a bit, he pronounced that it appeared to be a good and smooth sphere and that WE WAS GONNA FINISH IT! I muttered that I didn't want to impose on Pat (though I often do), but that if he found himself looking for a project in the coming months, sure, slap it on the mirror stand and have at it. That was outwardly. Inwardly I was thrilled. After thirty-seven years this long-forgotten mirror would finally get to serve its purpose. There was more to it than that, of course; this humble six-inch Pyrex disk was a tangible link to my faded youth.

Pat did some further testing at home, verifying that it was a fairly decent sphere and that I had come reasonably close to f/6, with it testing-out right at f/6.3. Following that conversation, I didn't give the mirror much more thought for a month or two. What with the coming of summer and the inevitable clouding of our skies, Pat did indeed decide he wanted an ATM project, and got seriously to work on “Old 37.” The shocker? When he rung me up shortly thereafter to tell me it was done. It turned out I had been a mere 2 – 3 hours from finishing on the August afternoon when I’d gone off to flirt with the girls in the chorus of The King and I. Talk about irony.

Given the convoluted history of the mirror, the rest was anticlimactic. The only real eye-opener was how scarce ATM parts (at least for smaller aperture scopes) are these days. I did quite a bit of looking around before I found a secondary holder and spider that I thought would do, a nice set-up from the 1800 Destiny folks. Their name may be odd, but their service and their products are outstanding. One thing I did different this time was that I bought a curved spider. That eliminates the diffraction spikes that I, after 32 years using CATs, now find distracting. The focuser to go with it was a 2-inch Crayford from Orion. I was astounded at the quality of this unit, especially given its insanely low price. Smooth as butter, but capable of handling a decent payload.

The tube came from Hastings Pipe Company, who mainly sell irrigation pipe, but sell to ATMs as a sideline. This length of aluminum tube was OK, and once painted looked good despite the fact that the ends were not quite as round as they could have been given the money I paid (just under 90 bucks with shipping for a 40-inch length of 7-inch OD stuff).

Primary cell? I’d horse-traded some items with a fellow club member some years ago and one of the things I’d received was an 80s vintage Meade 6-inch mirror mount. With some cutting and fitting and modifying Pat was able to get it to fit my tubing. The last piece of the puzzle was a finder, but I intended to keep it simple with a good, ol’ Telrad. A base came promptly from one of my favorite newer dealers, Agena AstroProducts. All that remained was to get Old 37 aluminized.

I chose a standard aluminum coating, and used the same firm as when I had my 12-inch Dob’s primary recoated recently, an outfit local to my area of the country. The 12 had come back in just a couple of weeks, and I was hoping to get the same service on the six, since, almost in spite of myself, I was getting excited about the “new” scope. Alas, the two-week turnaround I’d experienced with the 12-inch did not repeat. After five weeks or so, I called the coater, who sounded annoyed to hear from me, but allowed that it had already been shipped. The day Old 37 returned I was both thrilled and dismayed.

The coating on the 12-inch had been just about perfect, beautiful even. The 6? I wasn’t impressed. In addition to one large and obvious sleek, there was a spot near the edge where the coating was obviously thin. An email to the coater got a prompt if somewhat snitty reply. Surely, if there were anything wrong with the coating it must have happened during shipping. If I wanted to send the mirror back, he’d take a look at it. Since the problems wouldn’t impact mirror performance, I demurred.

I do not, frankly, believe the coating problems happened during shipping, but I am not sure, and for that reason I am choosing not to mention the coater's name at this time. I was mostly put-out because, despite the standard coating, getting the 6-inch done had not been cheap; just the opposite, and I felt that this small mirror—which was nevertheless important to me—had not been given the care I’d paid for.

The long wait for the mirror had not been all to the bad. Just like way back when, it gave plenty of time for putting the OTA together. One thing I knew was that I wanted to paint the tube white. In the Olden Days, all telescopes were white, and I wanted Old 37’s paint-job to reflect her heritage. I also asked Pat to do two sets or mirror cell mounting holes, one for visual use, and one for imaging. Unless you use extension tubes for visual observing, it’s necessary to be able to move a Newtonian’s mirror up the tube in order for the scope to reach focus with a camera. Pat asked “how far,” and I ciphered out how far up the tube the mirror would need to move to come to focus with my Canon DSLR.

This was important, because I envisaged Old 37 being primarily an astrograph. Sure, I’d use her visually occasionally, but I thought she’d be just about perfect for picture taking. I’d wanted something a little shorter in focal length than my C8 for astrophotography, but with more aperture and image scale than my small APOs. I’d been considering a short Mak-Newt or a 4-inch ED refractor. If the 6-inch would serve, that would be a whole lot cheaper.

If not that cheap. Not including the mount (I intend to use it on my Atlas mostly), and not counting the cost for a mirror blank which I already had (not cheap now), I probably wound up with about 300 bucks in Old 37, which is likely one of the reasons people are not doing more ATMing. It’s much more practical and economical to just buy. An 8-inch Synta Newtonian on a good (non-go-to) GEM can be had for 600 bucks. A Dob is even less. A nice six-incher from Orion, for example, is crazy cheap--less than 300 dollars at the moment. Is it any wonder most clubs have shut down their mirror making classes? Now, as I said from the get-go, I am hardly a grit ‘n glass madman, but even I acknowledge that with the death of mirror making something has been lost from amateur astronomy.

And, then, finally, despite the twists and turns and passing of 37 summers, she was ready. Pat told me to grab a mount and head over to his digs for First Light. I packed up the CG5 and drove across the Bay-Way way too fast. On the mount, Old 37 looked just beautiful. If you didn’t look closely at the GEM and with all its computer frippery, she fairly reeked “1960s,” just as I’d hoped. Now it was time. With a gibbous Moon hanging in the sky, that was the obvious choice as First Light object. I was not disappointed. In an Ethos eyepiece, the Lunar terminator was just dead sharp and lovely (and I imagined it would have been almost as lovely in my Edmund Ramsden). Despite poor seeing and intermittent haze, Jupiter was a welter of detail when the air would settle briefly. I was sorry Saturn wasn’t available; seeing the ringed world on this First Light Night would have tied the bow on the package.

Bow-tying, you see, was what this project was really about, muchachos. I think Old 37 will perform brilliantly as an astrograph, and will report on my success there when we finally get some clear skies again. However that goes, something important has already happened. This long unwrapped package has had the ribbon put on it. The circle has been closed. A link has been forged with the long-ago summer of ’71. When I look at and through my wonderful telescope, I feel again the excitement of jumping into my jalopy to tear across town to my girlfriend’s house, where we’d sit for hours listening to Woodstock and solving all the world’s problems. Most of all, it brings back those first-blush nights when the stars were new.

Next Time:  Amateur Radio and Amateur Astronomy...

Comments:
Hey, Unk, just wanted to say thanks for another great post. I love your writing--your experience is greatly appreciated but it wouldn't mean diddly without your enthusiasm, which seems to have only grown with time. Keep 'em coming!
 
Hi,

What a post, i really like reading into it. Having that kind of things that reaching 37 years old is just a manifesto that the owner of that telescope is taking his things well and intact. His discipline to his self and to the people that uses it..
Wow thats all i can say..
Keep up the good work..
I enjoy reading this kind of post article..
 
Hi,

I am a fun of telescope and I was happy reading your article. Hope I have that kind of telescope to keep on..

I love your article hope to read more on this blog...
 
I've been reading several of your old blogs. Mentioned it in another comment but I really enjoy your writing.

Your comments about your OM hit me a bit. My interest in astronomy is just about 180 degrees from yours. I started in ham radio, KA3GZV. My parents, especially my dad, went out of their way to encourage me in my hobby. I spent many late nights in the the early '80s, my high school years, banging away on the old straight key late at night trying to pull in that far flung DX on 40 and 80m.

I did have a "toy" scope probably similar to your 3" that was a public auction purchase. I never really did much more than look at the moon but I always enjoyed looking at the night sky, especially in winter when everything seemed so much darker and the stars brighter.

Reading this particular blog brought back lots of lost memories about my dad. He passed away a little over 2 years ago and never did get to look thru any of my eyepieces. I do however believe that he may now be the luck one having the front row seat for the view of the heavens.

I've since recently passed my Extra exam and like you it only took me 30 years to accomplish. In the big picture both telescopes and radios are essentially related...both electromagnetic receivers, just tuned to (much) different frequencies.

John Schnupp, N3CNL
Georgia, VT
 
Welcome to the Extra ranks!
 
Hi Unk,
So many similar but yet different memories brought to me by your great post from 1971. I was just out of the Air Force including a Vietnam tour. And a great blessing of a 1 year old baby boy Patrick not knowing that another blessing was coming next year, a beautiful baby daughter. I always loved Amateur Radio and Astronomy but only dabbled around the edges and never jumped into either with passion. I wound up with a passion for old English cars to my Dads (OM) dismay, he being a die hard Chevy man. On the note of our OMs mine was a simple but still inside a complex man. He never participated in my odd hobbies of radio and astronomy but was quietly and gently supportive of every new and crazy idea and hobby I dragged in. Now 44 years later I too reflect on 1971 thanks to your post and take stock of the passing years. My OM has been up there in those stars for 22 years and I still miss him. My mom joined him 11 years ago. Well, thanks to your post I feel the urge to finally get serious so I vow to get my amateur radio up and running (an old Kenwood) and get at least an ETX 125. I sold my Meade LX200 8 inch several years ago because it was too hard to set up and just sold my ETX 80 and ETX 90 to get a computer for my grand kids as the return to school this year.
Thanks for bending my path and giving me a great walk down memory lane. P.S. I had an "Unk" who was my hero and mentor in my early years. Not an astronomer but a naturalist who lived simply in a cool mountain cabin with two old maid Aunts. He could do anything in my eyes, trapping, fishing, gardening and telling me about every plant in the woods. Again Thanks Unk!
 
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