Well as per, ive not had much time to grind but ive made the most of the time I have and im now just short of the 12mm sagittal that I was aiming for!!!
Im still in two minds if I should go a little deeper before I cast my tile tool as its much easier to shallow the sphere off during second stage grinding than it is to deepen it if I go too shallow(need to cast a new tile tool and re hog out the depth again).My target sagittal for my focal length is 9.75mm so hopefully 2.25mm is enough extra depth to get me through second stage grinding but I may go to 12.5mm for extra security.the curve doesn't show up well in camphone photos but it looks amazing to the naked eye!!!!hopefully by the end of next week I will have cast a tile tool and started grinding with it :)
curve doesn't quite show in photos
close to 40 hours hogging to get to this point!!
tbh the hardest parts are yet to come.While hogging out is hard work its not particularly intellectual, anyone can do it with a bit of practice but the next stage will involve interpreting a ronchi screen to tell me if im grinding right so its a bit scary.
Big changes are afoot in my life too as im moving from west Yorkshire to Portsmouth to be with the gf full time so we are currently house hunting but think we have found a nice detatched bungalow with a garage which will be my grinding den!!this will put me further away from my mirror knowledge support base so may need to make a few trips back up north every now and again for council :)
nearly 6000 views now,well humbled.hope everyone keeps looking and hope to have another update in a week or so :)
clear skies Rich
addition: a better set of pictures showing the curve as it looked to have a flat/turned down edge in other pics