Not too shabby, classic Kiwi DIY spirit! Please do be careful not to get poisoned by whatever chemicals are used (particularly for the tinning, as that sounds potentially nasty)!
I guess the air down your neck of the woods is pretty clean so silver may last better than in city air, autumn farm burnoffs and diesel tractor emissions notwithstanding.
Quote:
Originally Posted by sopticals
Silvering attempted on 33" mirror. Afraid its not perfect, (and this my second attempt with chems just in from Angel Gilding [USA], first attempt produced an unacceptable "white bloom", so had to remove the defective coating using a silver dip cleaner.)
This current coating is reasonable for try in the scope, (again its not perfect, having a small area [see photo at 10.30] where the silver did not adhere,other than that the surface has good reflectivity).
Next time I attempt the coating will have to be more fastidious with surface preparation (cleaning), and do a partial mirror rotate during the actual "spray silver" process. Also I feel temperature and humidity play a part in how well the silver "takes". I think the high humidity of 97% when I made the first attempt may have contributed to the formation of the "white bloom".
I suppose the good news is that silvering ones own optic is an affordable option with each attempt costing around US$15 of chems. If I was to get a mirror of this size aluminized I hear numbers in excess of AU$1650 for a coating. Built my 33" dob for about what it would cost to get mirror alone aluminized. Big aperture astronomy is not just for "the rich of this world". After all isn't ATMing about "getting what you can't afford"?
Photos: before and after.
Stephen
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