Hi diyers, I am thinking of grinding a mirror. After reading a lot about it, I have concluded that I am a quite analytical person who gets obsessed with a project quite easily so I think I would be good at it. Everything I read tells me to start with a 6 or 8 inch. The problem is, I don't have any use for a scope of this size as I currently use a 12 inch. Why is it suggested to start small? Surely one uses the same strokes and the same amount of strokes so, theoretically, it wouldn't take any longer to do a 20". Also, surely measuring Sagitta and testing is easier, the bigger you go. Is it just the risk of screwing up an expensive large blank that makes people start small? My understanding is that there is not much chance of making a mistAke that can't be rectified by going back in grit and trying again anyway. I just figure, if I'm going to go to the effort of doing this, I might as well get an aperture upgrade out of it. What does everyone think of this. Am I crazy
