Meniscus mirror attempt #3: OH NO
…the cement form’s curvature isn’t right. I measured the sagitta (how deep the curve is in the middle compared to the edge) and it’s 1/16". it should be around 1/4". This would make a telescope that’s 12 feet long.
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAARGH
I CNCed mold’s shape wrong. I have two choices: I can either grind/sand down the edges of my cement form into a deeper curve (probably releasing tons of bad to breathe in dust), or start the process all over again with new wood.