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Alderney
20-05-2007, 11:13 PM
Hi Guys
A few nights ago I left my scope out under my patio to get in some morning viewing. When I tried Jupiter I couldn't understand why the view looked washed out as the sky and seeing looked great. I then checked the scope with a torch and found that a slug or an army of them had crawled all over my mirror.I tried as per advice on the forum, cleaning the mirror which at first I thought turned out well, then when I looked at Jupiter again I had a job to see any of the belts where as before they were clear. I called into BTOW here in Perth and had a look at the mirror on a new SW 10", and I could see right away that my mirror looked slightly cloudy all over. I don't know if I caused this when I cleaned it as it was my first time cleaning a mirror, or if some chemical in the slugs slime had effected the coating. Now to coating.
I called and spoke to Issac at Chi Qin Co and got a price to strip and recoat the mirror and with a protective coating. I also looked at Astro Optical Supplies site and their price for a 12" mirror coating is quite a few dollars cheaper than CQC but their site doesn't say anything about clear coating.

What I am looking for is if there is another way to clean my mirror other than with soapy water and sterilised water rinse. If not who would you advise would be the best to get my mirror coated.

Thanks Guy's

ballaratdragons
20-05-2007, 11:43 PM
EEK! Slug slime!!!!

I don't know if it contains an acid or some-such thing that would affect the mirror surface, but I would be trying anything to clean it before sending it off to be re-coated!

Google 'Slugs' and see if you can find out about what chemical is in their slime. Then find a site that explains how to counteract that chemical.

Starkler
20-05-2007, 11:52 PM
Someone told me that Astro optical dont do SiO overcoat and that would explain the price difference. Its worth asking.

I would try the washing again. I use dish washing detergent and it probably cant hurt to make a fairly strong soapy solution and a bit of a soak, just as long as you give it a thorough rinse under the tap before the de mineralised water rinse.


If the coating is ruined its worth pricing a replacement mirror. Andrews sell them, or conversely get the figure touched up before recoating :)

ballaratdragons
20-05-2007, 11:56 PM
From a website about Slugs:

Removing Slug Slime
You may have noticed a peculiar property of slug slime. It's really difficult to wash off your hands. Field Guide to the Slug explains why: "Slug mucus absorbs water, helping to prevent dehydration -- a serious threat to any terrestrial creature of aquatic ancestry. "This is one reason that slug slime is nearly impossible to wash off. Rubbing your hands under running water only makes it worse; the slime should be wiped off with a dry towel before you wash. Or try rubbing your dry hands together, in much the same way you'd remove rubber cement. The slime can be rolled into a ball and discarded."

Dave, You may be able to gently rub it off. Don't use any water!!!

Starkler
20-05-2007, 11:58 PM
:scared: How do you do that without scratching the mirror?

ballaratdragons
21-05-2007, 12:00 AM
Dunno Geoff :shrug:

Very gently :whistle:

Alderney
21-05-2007, 12:24 AM
Thanks for the input guy's, I don't think I will try the dry clean but I will try a stronger wash and if its still not good then Issac's price of $282 even with postage is a fair bit better than Andrews $699 for a new mirror. I will also get Issac to check the figure when he removes the old coating.

ballaratdragons
21-05-2007, 12:27 AM
:thumbsup:

Alderney
21-05-2007, 12:29 AM
Have to go now "Survivor Fiji"

casstony
21-05-2007, 02:08 PM
I keep a plastic shower cap on the top end of the dob when not in use, and a similar thing but made of towelling is always on the mirror end. (don't know what it's called - women put it on their wet hair after a shower). I leave the towelling cap on even when observing; air can pass easily and it should keep some crud out, but it would be quite effective as a slug barrier.