where to re-coat mirrors ?

Donmo · #1 12-08-2009, 10:18 PM

About 10 years ago I made a 10" refractor. It has 3 flat mirrors in it to make it more "compact". It was such a big job I lost interest in ATM after finishing it. It's now time to get it happening again but the mirrors need recoating. I'm completely out of the loop and need to know where I can get them done. Does any one know if I can get them done in Adelaide?
I know of Astro Optical in Sydney but I'd like to avoid packing and mailing 3 mirrors even though they're not that big (4' diagonal and a 5 and 8" flat)

Don

Satchmo · #2 12-08-2009, 10:36 PM

Try:

http://www.opticalcoating.com.au/default.htm

You will want to get some kind of enhanced coating. Three reflections at 90% reflectivity is only 72% transmission and then ( I assume ) another 16% light loss from 4 uncoated air /glass surfaces. This would yield about the same light transmission as a non-folded 7" refractor with high transmission dialectric coatings.

If you have to send them to Sydney use CQin Pty Ltd as you will get at least Quartz protected overcoating at 90% reflectivity.

DavidU (Dave) · #3 12-08-2009, 10:37 PM

Nothing in SA but everyone seems happy with Chi Qin
http://www.yellowpages.com.au/bi/chi...w-2774475.html

Welcome, I would love a pic of the scope you made !

fringe_dweller · #4 13-08-2009, 10:44 AM

Hi Don! and welcome to IIS

..further to our conversation, I remember now it was a division of AWA that used to do the defence contracts in adelaide, that Tony had an inside friend sneak his mirrors into the batches, 10 years and further back.
I spoke to a friend who works for AWA now, and he said they are solely an IT company these days and he had never heard of it, he has been there 5 or more years now.

if the good and extremely knowledgeable people of IIS, like David and Mark, cant help you find someone locally, nobody can!

by the way, nice to have a world renowned luthier (amongst other hats) on board!

Satchmo · #5 13-08-2009, 12:12 PM

Optical Coatings Associates ( which I supplied link for ) in Adelaide took out a half page add in Aus. Sky and Telescope within the last 12 months which is indicitive of a willingness to service amateur market. They do an enhanced silver coating 99% that might suit a sealed system like a folded refractor. Try them and see.

DavidU (Dave) · #6 13-08-2009, 12:15 PM

Quote:

Originally Posted by fringe_dweller

by the way, nice to have a world renowned luthier (amongst other hats) on board!

Is Donmo a luthier too?

MrB (Simon) · #7 13-08-2009, 12:30 PM

I have great respect for Luthiers.
My cousin's website: www.jackspiraguitars.com

fringe_dweller · #8 13-08-2009, 01:11 PM

Quote:

Originally Posted by DavidU

Is Donmo a luthier too?

Hi David, yes, just google Don's username

fringe_dweller · #9 13-08-2009, 01:16 PM

Quote:

Originally Posted by MrB

I have great respect for Luthiers.
My cousin's website: www.jackspiraguitars.com

Wow! love those aussie woods! ..my Donmo tricone has a mulga fretboard. and my single cone has a jarrah fretboard!, amongst other aussie woods, swamp and silver ash necks. your cousin is a true artist!

thanks for eye (and ear) candy ink!

fringe_dweller · #10 13-08-2009, 01:18 PM

Quote:

Originally Posted by Satchmo

Optical Coatings Associates ( which I supplied link for ) in Adelaide took out a half page add in Aus. Sky and Telescope within the last 12 months which is indicitive of a willingness to service amateur market. They do an enhanced silver coating 99% that might suit a sealed system like a folded refractor. Try them and see.

cool! didnt realise they were in adelaide from linked site, doh!

DavidU (Dave) · #11 13-08-2009, 01:39 PM

Ah THAT Donmo ! cool resinators !!!!!
More music industry on IIS

Donmo · #12 13-08-2009, 10:15 PM

Thanks for your suggestions good people.
I spoke to Chi Qin today and will contact OCA tomorrow.
When I was making this telescope quite a few people were keen to mention the light loss associated with 3 mirrors. I forked out for enhanced silver coating by some mob in Brisbane I think (something to do with the CSIRO?). The coating lasted about a month. To their credit they re-coated the mirrors but that only lasted another 6 months or so. That's one of the reasons I lost interest in the project. It was a great telescope while it was working though. The eyepiece comes out of the mount pivot so I can sit on a milk crate to do my obseving. It's in pieces now but I'll post some pics when I get it up and running again

Don

fringe_dweller · #13 13-08-2009, 11:21 PM

does Mathew Lovett of Telescopes and Astronomy down south at Ohalloran Hill get his mirrors aluminised locally? any experiences out there?

http://www.telescopes-astronomy.com.au/

http://www.telescopes-astronomy.com....ccessories.htm

Satchmo · #14 14-08-2009, 07:57 AM

Quote:

Originally Posted by Donmo

I forked out for enhanced silver coating by some mob in Brisbane I think (something to do with the CSIRO?). The coating lasted about a month. To their credit they re-coated the mirrors but that only lasted another 6 months or so.

Was it LASERDYNE?

I have never seen particularly long life from enhanced coatings although vendors that can do them are always very enthusiastic about them.

Quartz overcoated mirrors seem to get a very long life if looked after .

Donmo · #15 14-08-2009, 11:00 PM

Laserdyne. That's the one.
I think I'll go with "ordinary" coatings. They're exensive enough as it is and I just want a working telescope. It takes up too much room in my shed to not be earning it's keep.
I've got fired up and spent that last 2 nights looking through my 7" refractor. First time in many years. Not much has changed out there!
Don