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A NO-NAME TELESCOPE


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A NO-NAME TELESCOPE

 

Roughly two years ago I submitted this article to S&T. Due to space limitations, it was heavily edited, rewritten, and condensed.  Here is the full story.

Back in 2002, a friend gave me an old 8” Criterion Newtonian, circa 1963, as a wedding gift.  It was in a questionable, but useable state.  I set it up a few times but for the most part, it sat in storage.  I did discover back then that it had an old Cave mirror and not the original Criterion mirror.  When collimated, the images were outstanding.

Fast forward 15 years and plus one son.  He is a normal kid but goes the speed of light in all directions. He liked “big” telescopes. As a 5-year-old he could visually identify most of the planets through my scope. I could see (or hoped) that he had a propensity for math and science. I wasn’t to be disappointed.

A few years later I decided that I would fix up the old Criterion for his 10th birthday. In retrospect, I am glad I started many months prior to his birthday.  So, in April of 2016 I dusted it off and went to work.

Taking a closer look at it, I clearly saw that the declination axis was in need of some repair.  The bushings where trashed and the actual shaft was badly rusted.  I thought that I might be able to clean things up and get it working. Wrong!  Not only were the bushing trashed, the actual castings were pretty well wasted. So, my “new” grand plan was to make a completely new declination assembly.

That didn’t concern me too much in that I am fortunate to have a CNC shop as my means to make a living. I found some thick walled aluminum tubing in my scrap bin and began to draw out my plans for a declination assembly. Something whispered to me to carefully check out the rest of the mount. I listened.

I discovered that the remainder of the mount, the RA and drive assembly, were equally in as bad as or worse than the declination assembly. So, I began drawing plans for a right ascension axis as well. Back to the scrap bin for more thick walled tubing. I decided that I wanted to use whatever materials that I had on hand and do my designing based on material dimensions. I even had a left over 7.5” drive gear left over from my mount making days. I also had a surplus drive corrector circuit board that I was able to incorporate into the drive end of the unit.

While building the mount, I decided on a push-to and not a go-to. I did incorporate optical encoders on both axis in order to utilize some old digital setting circles that I had.  I wanted my son to learn the sky as opposed to him just pushing buttons, but I knew that to keep his interest, I needed some buttons for him to push! I figured that would probably serve him better in the long run. Aside from that, I have other scopes  with  go-to systems for when he needs a button “fix”.

Before long, I realized that I wanted to make a new sub assembly. That’s the lower assembly that the RA sits in and incorporates the azimuth and altitude adjustments. I located some surplus 5/8” aluminum plate collecting dust in the back corner of my shop.  After some planning, sketching, CAD work, and milling, I had some useable parts. Beneath the assembly, I cut a section for an old drive gear and made an azimuth adjuster.

 

 

I finally realized that I was building a whole new mount for my son.

 

The original pier and legs were pretty flimsy.   It was time to design a whole new setup to put this new mount onto.  But I really didn’t want the traditional aluminum leg castings.  I designed some hardwood (cherry) legs that I laminated cross grain for rigidity.

I am glad I did. The wood really dampens the system quickly. I also incorporated a 6” piece of well casing to attach the legs and mount to. I had the well casing powder coated a dark bronze. I added some brass accents for both protection and looks.

As long as I was going all out, I might as well design and machine some very nice tube rotating rings. I am glad I did!  They work great and really make things easier for a ten-year-old (and his old father). The rotating rings were a real challenge. I needed to purchase some aluminum plate for the rings and some additional plate to for fixturing purposes. I then CNC cut the outer and inner rings out. The inner rings are attached to the fiberglass tube assembly. The outer rings are (inner) lined with UHMW for smooth rotation.

 

Once things were well under way, I saw that a beat-up old OTA just wouldn’t do for such a nice, new mount. After removing all of the optics and components, I began on the tube. The tube was original and fairly well made and well beaten. I re-fiber glassed, filled, scraped, sanded, messed up and re-did, the whole thing. Upon completion, I took it to one of my vendors to have it painted. It is a very durable finish used in automotive finishes. It turned out looking like it was brand new again.

To top it off, I added my old Comet Catcher that I had restored years ago. About the time I thought the project was complete I realized that all of my aluminum knobs just didn’t look right.  I ended up making and knurling a number of knobs out of solid brass. They looked better that what I had originally made. But they really take time to make.

 

Update 2019- I replaced the Comet Catcher with a Stellarvue 80mm short refractor. It’s a better match for the scope and easier for him to use. And it provides great visual images.

I did add adjustable weights fore and aft on the OTA. They really help with balance issues. About the only thing I still need to do is to add a 2” focuser for my larger eyepieces.  The Criterion came with an old 1.25” Meade, rack and pinion.  I found a very nice 2” on Cloudy Nights’ classified.  I’ll install it soon.

I really can’t call this a Criterion any more. About the only thing left from its former glory days are the tube and the secondary. And the RA and dec setting circles. I am not sure what to call it!

I was able to complete about 99% of the scope prior to my son’s November birthday. Needless to say, my son was pretty excited about his “new” scope. I hope he still has it when I am long gone to remind him that his dad was just a geeky telescope maker.

 


  • zjc26138, wky46, stevew and 24 others like this


27 Comments

Great article, great machining and cool story.

 

Not the kind of wedding gift spouses usually go crazy over, but my best friend gave me a floor jack that gave me great pleasure and solid use for 20 years.

 

Not sure about it being a 'no-name' though. Few would turn down a Cave or a non-SCT Criterion. And that mount deserves to bear YOUR name.

 

I learned not to be a fan of 'starter' equipment in any hobby, after having suffered through same on several hobbies; flying, scuba, astronomy, target shooting, archery, automotive and general repair,s and others. It's a miracle my erected, over-magnified, miscentered 60mm Tasco on a despicably ineffective 'fork tine', gluey lubed mount didn't kill my interest completely. 

 

'Starters' can easily poison interest (and in firearms lead to deadly accidents). Very good to excellent equipment, even if outdated, can just as easily build interest. Rehabbed with a tube cut to the f7 Carton replacement and GSO rack, on a zero friction alt az made the Tasco into a scope I would be happy to lend to a beginner, along with an astroscan. Despite the aperture.

 

Yours will be a wonderful starter scope that can go another 50 years as a permanent one, or lead to bigger and better once your son learns the ropes and builds his skills.

 

 

Funny to see a Comet Catcher looking so tiny!

    • woodsman, StarChaser55 and quality guy like this
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clusterbuster
Jun 22 2020 11:02 AM

That is a Very Fine Telescope !

 Nice Job indeed.....

 Mark

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Supernova74
Jun 22 2020 03:13 PM

Nice looking scope indeed a work of art.its just as pleasurable just look at it in corner of living room just as it is to look through reminds of an old scope manufacturer here in London called fullerscopes 

>blink<

>blink<

 

Imagine being 10 year sold and having a scope like that, built & restored by your dad no less!

    • StarChaser55 and Astroman007 like this

Very nice it is !

 

Regarding the name, this is a quote from Joshua Slocum who rebuilt the Spray and sailed it single-handedly around the world. (end 19th century)

"Now, it is a law in Lloyd's that the Jane repaired all out of the old until she is entirely new is still the Jane."

 

Jan.

    • markb and StarChaser55 like this

Beautiful job. You put a few hours into that one!

Please come show it at Stellafane 2021! And bring the proud new owner along too. Jay

Belated Happy Father's Day to a super Dad! Your son is lucky to have you. I believe your presence in his life is programming him for success!

    • StarChaser55 likes this

Outstanding job!!

Fascinating! Great work!

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AstroGaston
Jun 25 2020 05:11 PM

Wow. What a fantastic gift!

That is absolutely BEAUTIFUL!  You didn't just do a good job, you did a magnificent job.  That is something to be proud of.  

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65&Counting
Jun 26 2020 01:32 PM

Gorgeous scope and you're lucky to have a son that enjoys these wonderful toys as he is to have a terrific dad.

 

Great work!

    • StarChaser55 likes this

It's always awesome to see Father-Son projects with passion towards building beautiful things - especially that one could just buy a telescope from the store

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Dave Mitsky
Jun 27 2020 12:07 AM

Well done!

 

That is beautiful.

Great article and an even better result.  As for a name, I'm thinking "LB Myers & Son" Newtonian.  It has a nice ring to it! 

 

Enjoy it and the time you will spend with your son using it!

The ingenuity of humans never ceases to amaze me, that is an art form and what a work of art!

I actually remember reading the article in Sky & Telescope.  Great restoration and your son can stand on the dog to help reach the eyepiece.  I really like brass way better than stainless steel!

    • StarChaser55 likes this

Beautiful scope and a wonderful birthday gift! 

So did you also put together all the optics inside the OTA and collimate it too?? This is a fascinating story. Thank you for sharing!!

Yes

I'm up for adoption. 

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philipdehazya
Jul 08 2020 02:05 PM

Fantastic workmanship! Bravo!

Amazing work. Your son will treasure this his entire life and the memories you make with him will be priceless!



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