I have a old Pro edger that's giving me fits. It's randomly crazing my AR lenses. I've been trying to find a flexible block that would fit the chuck on this old dinosaur of an edger, but all the ones I've found will not work. It has a Semi-Tech style receiver for the chuck assembly. Anybody have any ideas or can point me in the direction of a company that sells what I'm looking for. Or is there a way to retro fit the chuck to receive a different style block. THX!!!