57 hr hogging 5 lb 60 grit 1 1/2 lb 80 grit full contact between the tool and mirror focal length is longer but it is easier to finish first mirror, center depth ended up .180 going back to 80 grit to stare working down in grit size march 31, 3 month time but got there. just to let people know I am still at it thanks for all the in put it has sure helped