Quote:
Originally Posted by nightstalker
Hi guys , I've never tried mirror making but plan to soon , I have a 12" scope that I'd like to put a homemade mirror in one day but realise
thats a fair way off .
So for now I've bought a 6 " blank and materials to have a go at it .
As I built a test stand and started building a tester a couple of years back  I thought I'd build and finish the scope first so as to maybe move things along a little quicker .
I'll start a thread here sometime on how it goes and your sage advice is most welcome  |
Hi Graham, the 6" size is great to start with. My first mirror was a 5.75" and was a great exercise, but was I admit (in hindsight) a bit rough. However gave not bad views. In those days you started with a rough cut (about a dozen sided sawn) piece of 1" plate. I asked for a diameter of 6.25" hoping that by the time I had ground it into a circle it would have been 6", but lost a full half inch in the translation.
With your 6" blank I would suggest you make it to f10 as at this optical speed a spherical figure would be ok,and assuming your 12" dob is f5 then the focal lengths of both mirrors being the same, the 12" dob structure could double as a test bed for your 6" mirror.
