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Mirror scrub


Tweedledee
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Had a cleaning session on the Schmidt Newt mirror this morning.


I sterilized the sink and work area so it was clean enough for brain surgery, but decided against using the items to the left of the distilled water in this picture :D ...


Clean1a.jpg


 


I marked the outside of the mirror cell and tube so I could replace it in exactly the same orientation afterwards. The mirror in its cell came out of the tube easily after taking out 4 small allen screws. I left the mirror in the cell, it looked a right mess...


Clean1b.jpg


 


Filled the sink with tepid water and a teaspoon full of non-fragranced Liquid Soap Flakes.


Left the mirror in the cell and put the lot in the sink with the mirror surface about 30mm below the water surface.


 


I left it soaking for about 10 minutes with a bit of water agitation to help loosen debris. Then used lots of cotton wool balls, carefully rotating them to lift dirt up and away from the mirror surface whilst only allowing the weight of the wet cotton wool to bear on the coating. One ball per pass across the mirror. After doing this three times with water changes, the mirror was finally looking better. Several small areas around the edge still weren't perfect until I used a cotton wool ball soaked in 99.9% pure Isopropyl Alcohol. Rinsing with lots of distilled water and drying off with a hair drier had it looking great. I was satisfied that it was as good as it could be without re-aluminising. On hindsight it would have been wise to remove the hanging saucepans and cooking implements from above the mirror, but luckily no calamities :facepalm2: ...


Clean5.jpg


 


Took me a while to get the 4 screws in to hold the cell to the tube. It was a bit fiddly and I was worried about cross threading them.


Checked the collimation with a lazer and a collimation cap and decided it was about time I got a self centering adapter. So much movement in the fittings I could make the beam on the collimator reflector wiggle about quite a bit. Went online and ordered a Revelation adapter from Harrison Telescopes for just £19.94 including VAT and shipping.


 


Very pleased to get that job done. Might have a go at the corrector plate next.


 


 


 


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I feared the worst when I read the title :o :o :o

Nice job. :thumbsup:

Cheers, Graham. Well, it wasn't quite bad enough for the Brillo pads :D .

 

 

Always worth it i think Pete. Did you get the distilled water from eBay? I ask as its the same as the stuff i use and i got mine from there.

Yes, I saw your previous post Felix, and got "Triple Filtered, Double Distilled" from ebay. It's certainly not cheap is it :) .

 

 

What a difference and those pans look nice too :)

It's a good job they stayed above the mirror :o 

 

 

Always rewarding to have clean optics.

Glad it went well.

Jd,

Cheers James. The whole job took much longer than I had expected it to. The cleaning took a long time as I knew I needed to be very careful and then I spent nearly an hour cursing the 4 little allen screws back in to secure the mirror cell!!

 

 

Got those self-centering adaptors on both scopes, well worth it!, nice job well done. :)

Thanks Ron, thought they were a bargain price compared to some.

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It's very satisfying to have a clean mirror, it just looks so good.


I suppose it will need less cleaning than an open Newt, but like you say, you have the glass to do next.


 


It seems to me that they are a very under rated scope those Schmidt Newts, there was a 10" one on ABS for £250.


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