Compared to half a century ago we pretty much live in an astronomical COTS time. The vast majority of amateurs peer through equipment that is massed produced. Attending a BAS star party back in the 70s and 80s, one would find a fair number of the telescopes were fashioned by their owner. They ground the mirrors and constructed the mounts, displaying a range of frugality and craftsmanship in their implementation. Many clearly had taken "shop" as part of their secondary education and were comfortable turning out custom parts for their scopes.
One of those individuals was Charlie Cyrus who built a 10" Dobsonian. I will always remember the first time I peered through the instrument at M13 - I was blown away at how well it resolved the stars compared to my 6" telescope. When looking at the planets it always provided crisp views that spoke of the hours he had poured into sculpting the glass to his standards. Charlie was the epitome of an ATM.
When Charlie passed his good friend and fellow BAS member Dr. Richard Pembroke became the steward of his telescope. Richard was a passionate, respected amateur astronomer and well connected to the community of observers. As he contemplated downsizing in retirement he asked if I was interested in having Charlie's telescope. I immediately said yes even as I pondered how I could explain to my wife that I had another telescope in the garage.
For about 15 years I used the Cyrus scope as often as I could. Its additional aperture allowed me to track down multiple additional Herschel 400 objects and pick out more details among Jupiter's clouds and Mars' surface. It accompanied me to many Stellafane visits and Tuckahoe star parties, creating memories along the way. But time and use took its toll, and eventually the wooden Dobsonian mount became too feeble to properly support the optical tube assembly (OTA). I could almost hear Charlie saying, "OK Jim, it's your turn now to use some ATM skills to restore it!"
And so I set off on what would turn out to be a multi-year endeavor to give Charlie's scope continued life observing the heavens. I elected to replace the Parks tube that housed the mirrors since the focuser (which Charlie had made) was no longer usable with too much slop. Lacking machine shop skills, and no friends with that talent, I calculated that a sturdy "Sonotube" would be best since it was a material I could work with. I ordered a long, sturdy tube - thicker than a Sonotube to ensure support - and cut it to size. This was like pulling the thread that unzips the seam, because now the machined mirror cell had to be adapted to the new tube, or a new one made. It seemed that I would clear one hurdle and then have yet another technical challenge to address. But finally the new OTA emerged under my hands.
One of my primary objectives was to have the scope on a mount where tracking was feasible. My grand scheme was a Dobsonian tube cradle that could have a mounting plate affixed to it, permitting the OTA to move from Dobsonian rocker box to my Orion GEM, offering the best of both worlds. I made several attempts at it before finally facing the fact that it was not going to work - the Cyrus OTA was just too heavy.
Growing tired of having the OTA but no mount, I elected to contract the task of creating a Dob mount. I coordinated with a shop out in California about a year ago and ordered one of their products, hoping that I could add a Losmandy mounting plate to the tube cradle to permit me to attach it to my sturdier CGX-L GEM that I had acquired. I had hoped to have it by the Mars opposition last October, but that deadline came and went. Maybe by the Grand Conjunction in December, but that, too, came and went. Finally I received it in April and assembled the new Dob for the Cyrus scope.
The mount seemed adequate and I believed it would work out as I placed the OTA into its cradle. One issue I noticed quickly was that even though I had added additional felt liner, the tube would still slip down under its own weight. But that felt like a problem that could be fixed. With the Moon almost full it served as a convenient target to verify if the optical train was properly configured. I found that the mirror needed to be set back down the tube in order to achieve focus, but again, a task that was very doable.
Almost there! Or so I thought. The next free weekend I set about repositioning the mirror and adding additional felt when I noticed that the laminate on one of the wooden altitude bearings was separating. Indeed, the entire thing was coming loose and breaking. I couldn't believe it and contacted the vendor. Long story short, there would be no resolution from this person, and given the delays in receiving it I was not about to ship it back and have another year pass waiting and hoping for this individual to make it right. One benefit of my heart attack has been making it clear to me that every day counts.
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| Laminate Separation |
I decided to take off the Friday before the July 4th holiday and dedicate that 4 day weekend to making a tube cradle with an attached Losmandy plate that could support the OTA on the sturdier mount I had purchased - no more excuses! In some regards it reminded me of software development in terms of the life cycle - design, create, test, remediate defects you uncover during testing and try again. Finally, in the pre-dawn hours of July 5th, I got a true "first light" for my Cyrus scope restoration by imaging Jupiter for an hour. The detail it provided, along with the exciting prospect of having this wonderful instrument back, made it all worth while!
And now the refinement process has to happen, steps to take to make the telescope easier to use (because a telescope that requires a lot of effort to set up for a session does not see as much starlight). Inspired by some photos of HAL member Victor Sanchez's setup, I used last weekend to craft a "dolly" so that the entire rig can be rolled in and out of the garage. Next up will be adding a dovetail to attach a finder scope and hopefully a paint job to make it look a little more polished. The biggest lesson in this journey has been a better appreciation and respect for the talent, effort, and ingenuity that an ATM puts forth into their telescope - truly a labor of love from which I have benefited greatly. Thank you Charlie for leaving behind such a gift - I'm proud to be its steward and hope I'll pass it to another generation of stargazers one day!
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