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Refractor Glass

Started by thx1138, 06/06/2013 02:11PM
Posted 06/06/2013 02:11PM Opening Post
I am looking for a supplier for achromat glass (about 4" to 8" in diameter).
I am also looking for old and/or unmounted achro lenses of the same diameter.
And if anyone out there has experience in building refractors of around 6" to 8", I would like to hear about your experiences.
Thanks for any ones help, JohnD 8O
Posted 06/09/2013 02:21PM #1
I am aware that Newport Glass Works lists achromat glass kits from 4" to 8" on their website.
and scroll down the left menu until you reach achromat kits.
I don't have any recent experience ordering from them.
Posted 06/09/2013 05:23PM #2
Hi John,

I just completed a 10" achromat, and it came out great. The Bath interferometer says it's a Strehl 0.98 (about the limit for a doublet), 1/38 wave rms. I'm just having it AR coated now. So if I can give any moral support, let me know.

Before I found someone to safely AR coat it, I considered oiling it. So I've got a pretty complete set of Cargille optical coupling fluids. If you wish to oil yours, I can probably help there, too.

Have fun.


Posted 06/21/2013 08:48AM | Edited 06/21/2013 08:52AM #3
Here is an 8" F/12 I built back in 06. The OTA splits into three parts for easy portability and setup.


Attached Image:

klawson's attachment for post 147234


40 year old restored C14 with recirculating cooling w/Skywatcher DOB GOTO Conversion (CPC14)

10" F/15 thermally managed ATM Coulter Cassegrain mounted on a Celestron C14 wedge to GEM conversion

"Electro-DOB" mounted Sky-Watcher Evostar 150mm/1200mm ED Refractor

"Rescued" Craig's List Orion 120mm/1000mm Refractor


Posted 06/27/2013 07:17PM | Edited 06/27/2013 07:18PM #4
i'm doing a 5.8 inch f-15 lithrow cemented doublet 3/4 way thru grinding will be polishing when warmer its the middle of winter in new Zealand,

I want to mount on an heq5 so will be trying to save in weight etc

when I get a chance i'll show you the wedge tester and spherometer I made for the project which are simple but seem to do the job.

Have a go. picked up blanks 2nd hand for 180 dollars a bargain.