Cleaning your mirror with a steamer.

[Den]

Has anyone tried to clean their telescope mirror with Distilled water in a hand held steamer. You would not need to touch the mirror avoiding scratches. :question:

[LewisM]

I would be very concerned about 100°+ water vapour thermal shocking a cold mirror, let alone the very thin silvering and clear overcoating.

In general, DON'T do it.

[sn1987a]

Yeah give steaming a miss if it worked we'd all be doing it by now. I follow this approach https://www.youtube.com/watch?v=9Y8xFnXFVGQ

[dannat]

I would not have thought steam would crack a mirror or harm the coating (as long as it was applied correctly in the first place)
we placed many much thinner glass items in autoclave before for long periods & get very few breakages

problem with water is that it often doesn't remove much (dust which you can just blow off)-some deposits require a diff solvent to lift them, eg alcohol/detergent

[Den]

Thanks Guys,

I guess it works great in the shower removing mould and stains on tiles and glass. It would have been a nice easy way to clean a mirror.

Regards

Den

[LewisM]

Autoclave gradually comes to pressure/temp. A steamer is already at 100°C, and directing that onto a chunk of glass that may be at an ambient of say 18° is a differential of 82°C... not good me thinks.

You'd probably get away with it, perhaps a few times, but why risk it?

[Den]

I agree LewisM ,

I was going to preheat the mirror slowly with a hair dryer
then steam clean.

Another item I would like to test is this product
on a telescope from the local tip.

Link:


http://www.shieldnpeel.com.au/store/index.php?route=product/product&path=20&product_id=52

[MrB]

Another thing that may be worth considering is the steam is under pressure, blasting the dust, I would think this would have more potential to dig/scratch the mirror than a gentle wash?

[5ash]

Are you going to "peel clean it"?? A few years ago I saw such a cleaning method being advertised in the USA. I think it's on utube.
Hilip

[Den]

At the moment the mirror is still clean ( new scope ) with a little micro dust from use. I am researching non destructive methods at the moment. I may need to get a damaged scope from the tip and do some testing first.

Den

[Den]

Hi Simon,

Looks like steam is out to many people advising against it.
Den

[PeterM]

The method you saw was possibly using Collodian.
The article below from Cloudy Nights gives some good advice.

http://www.cloudynights.com/item.php?item_id=1304

[MrB]

Yep, I was just driving another nail in the coffin with another reason against ;)

[5ash]

No it's not collodion but a similar process to the one described ,but using a modern polymer sprayed on and peeled off. It's been used on the individual mirrors from the Keck telescope. Its described in the youtube video below. I believe the company is called Photonics.

Look on YouTube for "cleaning aluminium mirror with first contact polymer at vandenberg"

I did see it described and demonstrated at an astronomical products so some years ago in America.
Philip
Ps couldn't copy the link that's why I gave the video title.

[Den]

Hi Philip,

Check this product out.
I would like to test it on a old mirror.
Den



http://www.shieldnpeel.com.au/store/index.php?route=product/category&path=20

[Den]

Telescope mirror cleaning solution.

http://www.photoniccleaning.com/

[LewisM]

I would be wary of collodion and similar peel off cleaners too. Several reviews have cited removal of spots of transmission coatings on refractors, and some de-silvering on mirrors.

I am not russhing out cleaning my refractors with it.

[Den]

I agree,

I have access to a old dirty 4" mirror I may purchase the Australian

Shieldnpeel 1L pot and do many tests over 6 months and see the results.
Den

[5ash]

Hi Dennis,
It would be interesting to see how firmly it attaches to window glass. Suggest you spray it on a window with a spray bottle and leave a small attachment on the edge to make it easier to grip.keep me posted.
Regards philip

[Den]

Hi all,

This afternoon I did the first test on a old 4" mirror.
I steam cleaned for 10 min with normal tap water.
Because our unit has been used with tap water before.
I will get a new one for $20 for distilled water use.

On this mirror the coating stayed on even where the mold corroded the coating. The negative to tap water was it left some chemical residue behind this I was expecting.
I washed it off with hand cleaner soap on tap and rinsed off with distilled water.
I am deliberately doing this to see how durable the coating is.
This mirror survived.
Do not try this on a newer mirror until others have confirmed doing it with older ones first.
Now, if any one has got a old unwanted telescope mirror or lens and has a steamer give it a steam clean to see if you get the same results.
And post your results.

More testing to follow.

Regards
Den

[AG Hybrid]

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]

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

https://www.google.com.au/webhp?sourceid=chrome-instant&rlz=1C1ASUT_enAU507AU507&ion=1&espv=2&ie=UTF-8#q=exploding%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]

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 (http://www.shieldnpeel.com.au/store/index.php?route=product/category&path=20)
If this method has only minor adhesion, it should be a safer way of removing general dust.

Den

[mental4astro]

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]

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? :P

[Den]

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]

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.