how do homecast mirror blanks perform against professional ones ?

markuslebt (Mark) · #1 08-10-2012, 04:17 AM

hello there... been watching a website of a guy who bakes his own mirror blanks in a small kiln, size about 8-14inch so far. he uses simple glass plates he gets from thrift stores etc. bakes them together in his kiln, he even can make honeycomb-leightweight structure.

but how does such a mirror perform against a BAK7 or pyrex mirror u get in your regular skywatcher, GSO or celestron newton ? is the expansion a big problem ? anybody got any experience ?

of course this costs him time, but moneywise when youve got the kiln those blanks can be gotten for less than 50$. then some grinding tools and lots of time+ a faucault tester and youre in the business for making your own mirrors...

cheers Mark

markuslebt (Mark) · #2 08-10-2012, 04:19 AM

http://www.mdpub.com/scopeworks/hexagons/index.html

MrB (Simon) · #3 08-10-2012, 03:50 PM

I think the biggest factor determining the success of home cast blanks would be how finely annealed the blanks are.
If the annealing is good enough to be classed as fine or precision, and there are no bubbles/inclusions, then there is no reason the blanks couldn't produce a good mirror.

It is a very interesting link, thanks for sharing.