Sunday, May 3, 2015

The good, the bad, the ugly and the Dirty Harry

I'm going off the rails for this post....

Before I ever was a pinhole artist geek type, I was an astronomer.
While in the womb, my parents took me to dark places to sky watch so looking up has always been part of my life. After birth and throughout school my parents had no issue with waking me and my younger sisters from deep slumbers to go outside and watch lunar eclipses, meteor showers or to catch a glimpse of a bright comet.
I remember many nights watching the Milky Way from the roof of our barn, or my grandparents farm in the Piney Woods of East Texas. Black velvety skies were the norm.

In 1979 we even had a bulls-eye painted in our yard hoping that when Skylab crashed back to Earth, it would fall in our yard and we would forever be famous and $10,000.00 richer since there was a bounty on the first piece of debris turned in to the San Francisco Examiner.

The debris field was near Perth Australia, so we lucked out of that one!

Anyway, as time passed, I found myself the proud owner of a 10 inch f6 Dobsonian style telescope.
It was build by the soon to be notorious Dennis Zwicky of Sugarland Texas in 1989. I say notorious because Mr. Zwicky found himself in financial woes after I took delivery of my scope and he left a few customers in the lurch without their telescopes after he had taken their money!

This story is really long and convoluted, so I'll skip forward and avoid the long dreary tale of convolution with the scope and just say after having it redone, and giving it to my Dad 20 years's back in my possession and needs another makeover!


The original paint job was a plain red base with a blue tube....I repainted the scope shortly after getting it in 1989 to the Nazca lines you see above.
 Here's the other side of the scope.

The current configuration is 10 inch f5 mirror.....still good!


The bad is this is looking through the focuser and as you can see, things are not lined up. The scope is out of collimation so the line of sight and the photons coming in to the scope are skewed and not aimed directly to my eye.
If everything was happy, you would see concentric circles in this photo. "Houston we have a problem".

It just not a big problem...I can fix this easy enough plus there are much worse now we come to the ugly part!

And man is this part ugly!
After sitting in my Dad's shed for about 15 years, and then in my sister's garage in Houston for another 5 years...this is what the mirror looks like! It's scary! It has dust, dirt, some spider webs and mildew on it! Yuck!
You might not realize what you are looking at, but this is the 10 inch primary mirror that sits at the bottom of the optical tube and collects all the photons coming in and apparently a whole mess of dust and crap!
This is kind of gross, but not a killer since I can wash the mirror....although it needs to be re-silvered and the scope will be happy again.
I'm going to take this scope to a star party and put it through some tests and then re build the scope from scratch.

The plywood is d-laminating, big time... it's a wonder the screws holding this thing together even have something to bite into.....yes, it's really that bad. Part of the wood is dry rotted and I think the original builder used cheap low grade plywood so there are a lot of voids in the laminates.
I'll source some cabinet grade plywood for the makeover. Plus there are better and more lightweight designs to build.

What all this means is I have promised myself to rebuild this telescope and not make another pinhole box until the scope is finished.

This scope has been waiting too long and I'm finally going to make it happy again.

If you have any comments about lightweight designs, I'm all ears.

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