So you want a 16" f5 Mirror ?

[gaa_ian]

Where does one start in finding a 16" f5 mirror in Australia ?
I am looking at purchacing a 16" Astrosystems Truss tube kit.
Just need a good mirror to go with it without blowing the budget out of the water !
Any Ideas or suggestions ? (not a lot of help on the web)

[Vermin]

You go right here: http://deepsky.cia.com.au/optics/ and email Mark.

Highly recommended (Mark did my 16" f5), you are looking at about $3000 plus postage and insurance (was $300 from NSW to TAS).

As I have said a few times before the Telekit is quite large compared to an Obsession clone due to having the lower truss pole clamps on the inside of the mirror box. Just something to be aware of if you want portability.

[gaa_ian]

Thanks Vermin .. I will look into that !
A bit more than I expected on the mirror, but I am sure they are superb !

[ausastronomer]

As good as it gets !!!

CS-John B

[Starkler]

If it doesnt have to be f5, you may be able to source a 2nd hand Meade 16" f4.5 mirror which were reasonably commonplace. I hear these are of variable quality from excellent to woeful.

[cometcatcher]

How do you feel about grinding one? Cost me about $600 complete to make a 39cm f5.4.

[gaa_ian]

That is quite a difference Kevin, how long did it take you ?
Is the mirror still in use ?

[ausastronomer]

Grinding a fast 16" mirror as a 1st mirror ? good luck :)

CS-John B

[cometcatcher]

It's still in use more or less. I have to get another flat for the telescope though.

It was ground from lightweight 30mm plate glass. Grinding on and off took about 6 months. Total actual grinding/polishing time was 88 hours not including testing or cleaning up etc.

I don't see why the average person can't make up to at least a 20 inch by hand, maybe bigger. But if no mirrors have been completed before then it would be a good idea to "practise" by making a smaller 8 or 10 inch first, just to get the hang of it.

It's also a good idea to keep at it an hour or two every day until finished. The big mirrors can be heavy and the polishing stage can have a fair bit of resistance so it's important to keep muscle tone up. I developed some good size muscles after I finished it! Although infortunately also some RSI. I think my technique could have been better.

[gaa_ian]

That looks like a great labour of love Kevin.
Unfortunatly for us we do not have the time for this, most people in the club work long hours, with the major employer in town being a 24/7 operation.
We will end up buying one, just have to get it at the right price !