Cleaning a 16" primary mirror

Gem (Grant) · #1 10-09-2013, 07:14 PM

Hi all,

I have a 16" dob that has a thin layer of gunk that needs cleaning. It isn't just dust. A 16" mirror is quite large and heavy to try to soak in a sink or tub (as I have read most people do). In addition, there is a fan that is probably attached to the back of the mirror.
Ssooo.... I was wondering if anyone has cleaned a mirror using photographic lens cleaner and lint free wipes? Can it be done? I realise GSO mirror are fairly thinly coated so I wanted to ask around before trying anything.

Comments/suggestions appreciated!

Lee · #2 10-09-2013, 07:45 PM

How about sitting it somewhere outside and washing with a hose/cotton balls, then a distilled water rinse....

dannat (Daniel) · #3 10-09-2013, 08:53 PM

Yes I've used zeiss lens cleaning wipes (similar to soaked lens tissue )
Then wipes dry with a soft cloth
Make sure the tissue is fairly wet so as to not scratch the coating

Hans Tucker (Hans) · #4 10-09-2013, 09:19 PM

Quote:

Originally Posted by Gem

Hi all,

I have a 16" dob that has a thin layer of gunk that needs cleaning. It isn't just dust. A 16" mirror is quite large and heavy to try to soak in a sink or tub (as I have read most people do). In addition, there is a fan that is probably attached to the back of the mirror.
Ssooo.... I was wondering if anyone has cleaned a mirror using photographic lens cleaner and lint free wipes? Can it be done? I realise GSO mirror are fairly thinly coated so I wanted to ask around before trying anything.

Comments/suggestions appreciated!

In case you might want to rethink the photographic lens cleaner idea there are other options.

Came across this when I was thinking about cleaning a Mewlon mirror

http://www.skyandtelescope.com/howto...91.html?page=3

and Mike Salway wrote and posted this procedure on IIS

http://www.iceinspace.com.au/63-345-0-0-1-0.html

The Mekon (John Briggs) · #5 10-09-2013, 09:20 PM

Quote:

Originally Posted by Lee

How about sitting it somewhere outside and washing with a hose/cotton balls, then a distilled water rinse....

I'll second that. My 18" is full of electronics, fans, drives in the base, and I have washed the mirror with warm water + detergent then rinse with distilled.
Place scope outside, at about 30 degree elevation. Plastic sheet under mirror box to catch and drain water away. Done on a nice warm day, even if some water gets near the electrics, it will not matter.

Logieberra (Logan) · #6 10-09-2013, 09:26 PM

I also followed Mike Salway's directions when I owned a 10" newt. Great SOP: http://www.iceinspace.com.au/63-345-0-0-1-0.html

sn1987a (Barry) · #7 10-09-2013, 10:08 PM

Quote:

Originally Posted by The Mekon

I'll second that. My 18" is full of electronics, fans, drives in the base, and I have washed the mirror with warm water + detergent then rinse with distilled.
Place scope outside, at about 30 degree elevation. Plastic sheet under mirror box to catch and drain water away. Done on a nice warm day, even if some water gets near the electrics, it will not matter.

Yep!

Gem (Grant) · #8 10-09-2013, 10:57 PM

Thanks all. Outside sounds a good option - for some reason it never occurred!!

I had read Mike's method - I was just a little apprehensive about the size of the 16" mirror and the size of my sink. The thought of using lens cleaner appealed to my sense of taking apart of the least things (and thus reducing the chances of things going wrong on reassembly).

Thanks!

Satchmo · #9 11-09-2013, 12:05 AM

And the GSO 16" mirror are glued to the mirror cell with silastic so you would need to fit the mirror cell in the sink as well

AG Hybrid (Adrian) · #10 11-09-2013, 12:12 AM

Or you cut the mirror free from the cell...

Gem (Grant) · #11 11-09-2013, 06:47 AM

Hmmm... those Zeiss wipes are sounding more appealing now!!

Shiraz (Ray) · #12 11-09-2013, 09:44 AM

if you do clean it outside, be very wary of focused sunlight.

BEVAN5433 (BEVAN) · #13 11-09-2013, 09:56 AM

I have used the 30deg. angle outside method. I placed a small towel at the bottom of the mirror to protect elect etc .found my self two spray bottles.
THE TYPE WINDEX is applied in.
BOTTLE 1 2 TABLESPOONS ISOPROP ALCOHOL.
2 DROPS ONLY DISH CLEANING DETERGENT
FILL WITH WATER
BOTTLE 2 DISTILLED WATER

APPLY BOTTLE 1 SPRAY AND USE COTTON W00L SOAKED IN LIQUID TO WIPE SURFACE GENTLY
REPEAT SPRAY AS REQUIRED
APPLY BOTTLE 2 SPRAY UNTIL MIRROR IS RINSED
REMOVE TOWEL WHEN MIRROR IS FINISHED DRAINING

NO MIRROR REMOVAL NO EXCESS WATER LIKE NEW MIRROR

BEVAN

AG Hybrid (Adrian) · #14 11-09-2013, 10:23 AM

Quote:

Originally Posted by BEVAN5433

I have used the 30deg. angle outside method. I placed a small towel at the bottom of the mirror to protect elect etc .found my self two spray bottles.
THE TYPE WINDEX is applied in.
BOTTLE 1 2 TABLESPOONS ISOPROP ALCOHOL.
2 DROPS ONLY DISH CLEANING DETERGENT
FILL WITH WATER
BOTTLE 2 DISTILLED WATER

APPLY BOTTLE 1 SPRAY AND USE COTTON W00L SOAKED IN LIQUID TO WIPE SURFACE GENTLY
REPEAT SPRAY AS REQUIRED
APPLY BOTTLE 2 SPRAY UNTIL MIRROR IS RINSED
REMOVE TOWEL WHEN MIRROR IS FINISHED DRAINING

NO MIRROR REMOVAL NO EXCESS WATER LIKE NEW MIRROR

BEVAN

I'm not sure why you typed that all in capitals and spell W00L with two zero's but I will genuinely give this approach a try some time. ALSO WHICH LIQUID SOLUTION IS THE COTTON BALL SOAKED IN? THE SAME AS BOTTLE 1?

RAOARRR!!!!

BEVAN5433 (BEVAN) · #15 11-09-2013, 04:44 PM

BOTTLE 1 has the detergent (a small amount is all you need) .This is used first off, on the cotton wool. the alcohol IS ALSO IN BOTTLE 1 Spray surface of mirror until water is running off before starting to wipe with the wool also wet previously. I was in a hurry this morning that was the reason for capitals .In my Quantum world I often substitute zeros as REQUIRED .
Lighten up.
cheers BEVAN

BEVAN5433 (BEVAN) · #16 11-09-2013, 04:47 PM

BOTTLE 1 has the detergent (a small amount is all you need) .This is used first off, on the cotton wool. the alcohol IS ALSO IN BOTTLE 1 Spray surface of mirror until water is running off before starting to wipe with the
wool also wet previously. I was in a hurry this morning that was the reason for capitals .In my Quantum world I often substitute zeros as REQUIRED .
Lighten up.
cheers BEVAN

GrahamL · #17 11-09-2013, 07:45 PM

My 12"mirror is held to the cell by Velcro and as such is very difficult to
remove , so I flip the mirror box a little past 90 and put a bowl of some description underneath, THE very best bottle I've found to apply the first rinse ,or second for that matter is one of those flat shaped cappilano honey bottles they really push a decent stream of water onto the surface and remove the nasty before stuff before any sort of wipes go near the surface , I found the average little squirty bottles mostly useless for getting rid of bigger contamianants .

BEVAN5433 (BEVAN) · #18 12-09-2013, 11:29 AM

The spray bottles if large enough deliver adequate water to the surface.
THE COTTON WOOL DOES THE CLEANING not the spray.The sprays ensure water is not running everywhere into your electrics and allows quick drying
if you use a Towel PLACED IN THE GAP AT THE BOTTOM this also prevents water going into unwanted places. Over 30 years I HAVE TRIED almost every method possible the above allows me to clean a 16" mirror in less than five minutes
cheers Bevan