John Baars

A visit to the unique 9 inch Unitron Polarex

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by , 11-25-2018 at 07:08 PM (1600 Views)
Quote Originally Posted by John Baars View Post
Last friday 03-23-2018 I had the opportunity to visit the one and only 9 inch Unitron Polarex telescope in the world.

Thanks to Dave Komar, who pointed me out the whereabouts of this giant telescope (several miles from my hometown!) , I was able to contact the owner. The owner tells us via Dave about the amazing rescue from the scrapyard and demolition on his site: Polarex – Unitron Model 900 – Unitron History Project

Quite a remarkable and readable story. The owner told me that the rescue was no sinecure, since the telescope parts were separately found in several old buildings, partly covered under blankets or a thick layer of dust. The scope had never seen assembling. Almost unrecognizable, he didn't even know if some parts belonged to it or not. The caretaker of the square half a mile terrain couldn't help him either. And all that under the blazing heat of the Japanese sun. Luckely he was there.... expecting to find a six incher, and found this... All buildings of the old place have been removed by now.

Restoration and assembling of the 00-1989 marked giant took place at Technical University Delft, and being in the hands of the professor (owner) is all you want if you are a telescope that wants to be restored. Like many private owners of very big Polarex telescopes, the professor likes to keep low profile, so I didn't know if he had time for me as a simple amateur-astronomer/ tourist. Being a visual observer with a preference for refractors and living "around the corner" helped a lot.

So there I was. The professor picked me up at the university's parking lot and after passing some security doors I saw the giant in the large assembly hall.

I was amazed. "What a monster", I mumbled.

The professor told me that the straps of the lifting crane are for his own and my security.The mount is not bolted to the floor... In the base lies 881 lbs of lead in small portions, for low gravity point reasons. It took the owner quite some time of cleaning, polishing and puzzling to refit all parts. There was no manual and the majority of the parts were not assembled. One very very big puzzle! His search through the old Unitron terrain must have been very thorough, because no noteworthy parts had to be made. The 55 lbs lens is in the UK, where he lives nowadays (good thinking), and he has a 20 feet dome ready installed for action. "First thing I am going to do when I have the telescope operational in the UK, is to take a chair, sit beside it and enjoy the beauty of it", he trusted me. I think I would do the same after many years of restoration.

The more than 160 lb telescope operates very smoothly, nothing could be heard as I slewed it a few degrees around. The only way I could tell was by looking at the red control light and seeing rotate the crown-axis that drives the worm. What a difference to my own GPDX mount! Worm and worm-wheel are extremely fine and have many more fine teeth than my own. I forgot to ask how many...sorry. The lens is replaced for dummy-weights to keep him balanced. Lens is waiting for its tube in the UK!

Four brass rods secure locking and fine tuning RA an Dec axles. Driving train of RA axis is seen here.

This is me actually operating the telescope. It is a very simple handheld controller really. "forward", "reverse", "stop" and an old fashioned counter with a small wheel to regulate the speed. That's all. Look at the size of it all. I am 6 feet tall.

Nice posing. Looks like I am switching something. There is nothing te be switched over there I am afraid:-)...little joke of the professor and me.

Put to enthusiastic amateur-astronomers together and a half an hour photo session becomes a two and half hour visit. All nice things come to an end. The professor insisted on me coming back soon, before the Unitron makes his final trip to the United Kingdom. I will.

Within months this Unitron will find its new home in the United Kingdom. As a planetary-fan the owner will use this mastodon frequently. I'm glad he will. I wish him many happy observing years in the future. And many thanks for allowing this visit.

Special thanks to Dave Komar who put me on the right track, thanks Dave!
helicon64, combat48 and SpyderwerX like this.
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  1. helicon64's Avatar
    Fascinating story of the resurrection of the scope John. Quite a beast there.
    combat48 likes this.
  2. combat48's Avatar
    Great article and photos, John! Wish I could have joined you!!

    As an update, according to the latest from Alex, the scope was successfully moved, but set-up was delayed due to some medical issues. Alex hopes to have the scope up and running over the Christmas Holidays! Will keep you updated.

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