Cleaning your mirror with a steamer.

[AG Hybrid (Adrian)]

Looks alright. Modern mirrors and skywatcher mirrors in particular are over-coated with hard quartz (SiO4) and Titanium Dioxide (TiO2). I'm sure the coatings can handle a little steam. I've washed my mirror 4 times with kitchen detergent and there is absolutely no sign of the coatings degrading at all.

Not sure why people were freaking out regarding a little steam. Pyrex doesn't explode or shatter so easily.

[LewisM]

Originally Posted by AG Hybrid

Not sure why people were freaking out regarding a little steam. Pyrex doesn't explode or shatter so easily.

Not sure if that was sarcastic or not, but just in case, enjoy:

https://www.google.com.au/webhp?sour...loding%20pyrex

Note, Pyrex has not exploded upon shock heating since changing from borosilicate gass to soda-lime to as great an extent. BUT, to my VERY limited knowledge of telescope mirrors (I don't dablle in reflective arts at all ), they ARE still composed of borosilicate.

Just like the pyrex cookware, the stress SLOWLY "accumulated" in the crystalline structure through repeated use until it finally let's go (kind of like a Prince Rupert's Drop - https://www.youtube.com/watch?v=xe-f4gokRBs)

Anyway, YMMV, but if it were me, no way José

[Den (Dennis)]

Hi LewisM,

Great video,
I see your point that's why more testing should be done. And agree you may get " YMMV " varied results, that's why I stated using old mirrors and not much loved newer ones.
Soon I will test the;
http://www.shieldnpeel.com.au/store/...tegory&path=20
If this method has only minor adhesion, it should be a safer way of removing general dust.

Den

[mental4astro (Alexander)]

No, it's not a great video. It has nothing to do with steam cleaning a mirror. Wrong context.

I use a commercial grade steam cleaner in my work everyday as a dental technician. Have been using steam cleaners for over twenty years in my field. Our work entails producing very small, fine pieces that are sensitive to heat, so it is important to understand the heat source and its application. If steam cleaning was a problem I certainly would be encountering it. A tiny slither of glass is much more sensitive to steam than a bloody big block of glass, Pyrex, borosilicate, whatever. And like any tool, use it incorrectly and you will get trouble.

I've cleaned every single one of my mirrors with my steam cleaner. From my 114mm to my 17.5". Never a single problem. I still steam clean them.

The amount of energy involved is firstly very small in the jet.

Second, the nozzle is a greater risk to the mirror than the steam from scratching, so you don't even have the hottest part of the steam outlet on the mirror surface because the risk of scratching the mirror by a careless move of the nozzle is just too great.

Thirdly, the jet of steam is waved across the face of the mirror - you just don't hold the nozzle in the one dumb spot for any extended time anyway. You are not cleaning algae from a sidewalk.

The only problems with steam cleaning mirrors is waiting for the boiler to reach temperature, and the larger the mirror the longer it takes to cover the area.

If you are concerned about the coating coming off, yes, it can happen, but less so than with mechanical washing AND if the surface if the coatings are damaged in the first place. And like I said, I've cleaned and continue to clean my mirrors with steam.

[AG Hybrid (Adrian)]

No, my post was not sarcasm Lewis. As Alex has confirmed pyrex telescope mirrors due to their size, thickness and density are far more resilient then you give them credit for.

However, if we were talking about plate glass sandwich telescope mirrors you may have a leg to stand on. Sudden changes in temperature of a couple hundred degrees i.e. during a chemical wash to apply new coatings, have been reported to actually shatter one of those mirrors.

As you said you don't have experience around maintaining reflectors. Save it for the refractors. BTW when are you selling your Tak?

[Den (Dennis)]

Thanks Alexander and Adrian for your input. Perhaps there are others doing this as well.
Alexander, do you use distilled water or normal tap water.

Den

[mental4astro (Alexander)]

Always use distilled/demineralised water, even if your machine is a modest little domestic one. Tap water will not only shorten the life of the machine (by more than half!), but the sediments and deposits left by tap water will contaminate the steam and the job you are cleaning.

I have had my current steam cleaner for close to ten years now. Only ever use distilled water. Tap water would have killed the machine in under one year.