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Cleaning an ATM mirror

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8 replies to this topic

#1 JohnH  Happy Birthday!

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Posted 09 September 2019 - 03:59 PM

Getting back to my 121/2" homemade mirror after a spell of several years with it stored away.

 

 

I can see dust and some larger particles on it, in spite of it being inside a closed Tupperware container taped shut.

 

 

I want to get back to this project now that I have interest in this again but where to start?

 

 

 

A. Hose it off outside for 15 minutes?

 

B. In a sink after soaking in a mild soap solution?

 

C. using about 20 Zeiss lens cleaning tissues?

 

 

Or a combo of the above?



#2 bobruben

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Posted 09 September 2019 - 04:13 PM

Avoid hard things like sinks, in case the mirror slips.

 

A Presoak in water, followed by gently hosing off any crud.

 

Four drops of Dawn in gallon of water is soapy enough. Clean fingers with a very light touch in the soapy water can remove stubborn schmutz, don't bear down!

 

Rinse with water, then distilled water when done, then incline the mirror so the water rolls off.

 

Fold up lens tissue to suck remaining drops by capillary action, without applying any pressure to the mirror.

 

Don't drop it.


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#3 Garyth64

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Posted 09 September 2019 - 04:14 PM

There online videos for cleaning mirrors.



#4 havasman

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Posted 09 September 2019 - 04:19 PM

Start with a Giotto Rocket Blower and blow off the surface. Most particles will be removed. If more is required (it'd be surprising given that the mirror can't really be dirty having been sealed up) then use this method - https://www.youtube....h?v=9Y8xFnXFVGQ

 

It has become the de facto standard for most CN members, it seems. It is safe and works very well. I depart from it only in that I do not like the hard sides of a sink and instead clean all my mirrors outside on the driveway with a plush folded towel under the mirror with it propped on a 2x4 board for drainage.

 

The whole cleaning process takes @ 10 minutes with much of it taken up gathering the materials.

 

As always, the 1st major step in primary mirror cleaning is to very seriously question whether it actually needs doing at all. Usually it does not.


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#5 gr5org

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Posted 09 September 2019 - 04:51 PM

Is this a coated mirror or uncoated at this point?



#6 JohnH  Happy Birthday!

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Posted 09 September 2019 - 10:38 PM

Uncoated and partly parabolized



#7 BGRE

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Posted 09 September 2019 - 10:49 PM

An ultrasonic cleaner works well on uncoated elements.



#8 MKV

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Posted 09 September 2019 - 11:58 PM

Go to an eyeglass shop and get some Zeiss lens wipes. Rinse your mirror with distilled water and make sure it's free of any dust aprticles. Then stand the mirror up on its edge and let the wate rrunn off. Pad the rest of the beads dry with lens paper as already suggested. Lay the mirror down and use the wipes in the folded shape as they come out of the package, and gently glide them over the mirror -- one wipe per stroke -- with the folded (roudned edge) in contact with the mirror. No pressure, just contact. 

 

Wipes are cheap, leave no streaks and are designed for lenses and mirrors.

 

https://encrypted-tb...NGW3Og&usqp=CAc

 

 

 

 

 



#9 dave brock

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Posted 10 September 2019 - 05:47 AM

Uncoated and more polishing to come. Wipe with wet tissue after a water spray.


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