Mirror Cleaning advice needed

[Davekyn]

Hi,
after reading many posts in here on cleaning mirrors, I have decided to clean my 12" Dobsonian Mirror as well as my secondary. Here is my situation so far.

The water in our Dam is like at 9% with most of us using bottled water rather than out of the tap. Q- Would this water be ok to soak my mirror in?

Q-is it ok to add a few drops of dishwashing liquid to a sink/Basin half full of water for soaking my 12" mirror?

Q-Should I keep the water warm or cold?

For rinsing I have aquired a distiller from a friend who ussually supplies me the odd drink now and then. I will be making up about 18litres (two buckets of pure distilled water) I'll glad wrap the buckets untill I have heaps where upon I'll fill a 2litre bottle for pouring over the mirror and finally using a Bulb blower to remove the last droplets as well as stand the mirror up on its side with some paper towels for drying (which will be replaced several times)

Q-Rubbing!!!! Is it ok to lighty brush wet cotton wool clumps (under thier own weight) over stuborn spots?

Any advice on my proposed method would be greatly apreciated. (I was smply going to do the same with the secondary along side the main during the whole procces making sure to mark the alignment points to assist with collimation after cleaning.)?????

Cheers
Dave.

[DavidU]

Don't use the dam water as it have dust in suspension ( abrasive) if you have plenty of distilled water, use it. I like to have it luke warm with a few drops of detergent. you can softly drag soaked cotton balls across a stuborn stains although as lightly as possible.
After rinsing I get pure tissue ( non scented non colored etc) and shape it into the shape of a pensil and touch each drop on the surface with the tissue and their gone. Just a quick blow with a hair drier (a clean one, no dust etc) to make sure it is 100% dry.
good luck

[Davekyn]

Thanks Dave,
will do with the distilled water then. "Pure Tissue"? will look into it. Many Thanks.

[astro_nutt]

Hi Dave,
just a couple of things worth considering...
make sure the sink/basin is scubbed clean of any build-up such as calcium, lime etc then a final go over with metho..I have the water warm to start, place the mirror in, then add more hot water to bring the temp up gradually to about 40C, then mix a few drops of detergent in a cup of water before adding it in...allow the mirror to soak for about 10 mins, give it a swish around then let it soak again for another 10 mins. Hold the mirror up on a 45 degree angle when you drain off then rinse with warm water then distilled water. Dry off using a rolled up plain tissue and touch the drops only! Allow to cool befoe re-installation. Don't worry if a few specks are still on the mirrors surface..it shouldn't degrade the image.
Also make sure you have nothing near the sink/basin which could do any harm..soap holders, scrubbers, pets, etc and do take off any rings, etc.
Cheers!

[Davekyn]

Thanks! I am now glad I put this post in whilst distilling. Excellent info; much of which I would of missed rushing into it. I know that many believe that the best method is not to clean it and to take preventative mesures in the first place, however as a newbie, I ended up facing my scope into some windy situation out in a dust bowel. A few sessions like that outin a dry paddock soon has the mirror looking slugish with a new coating you don't want. I found using a dust filter like dust cover on the bottom helps heaps. Open country spaces are really great, but with dry weather about, it's amazing just how much craps can end up in your tube. I am much more carefull now.:)

[dannat]

I used tissue on my mirror & it left a mark - it was lens tissue
I have since used a lend brush / camel hair- if possible lightly brush while under water

[Batfink]

Here is a link to a video showing how to clean a mirror, this guy makes it look easy and says that too many people are over cautious, he uses nothing more than tap water, his fingers and a few drops of detergent.
have a look and see what you think.


http://www.youtube.com/watch?v=9Y8xFnXFVGQ

[erick]

Get a truckload of distilled water and follow these directions:-

http://www.obsessiontelescopes.com/learning_center/cleaning_mirror/index.html

Seems to me that one has to be careful but not over precious. Get as much loose stuff off first with blower bulb and clean water. Then soak in warm clean water with minimal detergent. Clean cotton balls drawn across surface in straight lines under their own weight. A new ball for each line. Wash off. Rinse with distilled. Stand on edge with towel. Use tissues rolled to points to lift off remaining droplets.

Yes, might be a few streaks and spots remaining. Don't worry about them.

Major risk is the potential damage due to banging, dropping, falling over, scratching with rings etc., not the washing process itself.

[dannat]

Peter - i thought the same & was not over cautious - rubbed it with ds H2O & few drops detergent - y lend cloth somehow (don't know how) damaged the coating - though the coating was old & probably had some damage

[DavidU]

The idea of the tissue wrapped up to the shape of a pencil is that you just touch the drops of water with it and you remove the drop with out touching the mirror surface.This is how I do it anyway.

[Batfink]

Oh Daniel now you've got everyone worried about cleaning their mirrors again:lol:

[Davekyn]

Great Links! I kind of feel foolish taking all this time to distil water now:rolleyes:. Now that I have started the process, I figure I will finish distilling anyways. I can recomend not to use a lense pen like I first did :eyepop:,I don't know what I was thinking.

[Roger Davis]

So does your mirror have a hardened overcoat? Say quartz?
Don't get too vigorous with the scrubbing brush until you know!
A straight aluminium coating or one with a standard overcoating will scrub off if you use too much elbow grease! There have been other posts on this in the past.