Grinding a 25-Inch F3 Telescope Mirror: Thinning and Flattening the Back. Gordon started with a 2" thick telescope mirror that weighed about 70 pounds. By thinning the blank, he's lightened the mirror by about 20 pounds! This video explains how he ground off the excess glass and flattened the back to begin fabrication of this F3 mirror for one of Waite's "feet on the ground" Renegade 25" telescopes!
Tags: Grinding a 25-Inch F3 Telescope Mirror: Thinning and Flattening the Back, astronomy, telescope, telescope making, mirror making, amateur telescope making, atm, telescope mirror, renegade, mirror grinding