I'mI in the process of beefing up my grinder and am making a new flat platten for it. My old flat platen was only 6" long and caused more headaches than I care to say trying to grind a longer blade flat. To solve that I bought one of those 15" glass platen backers on usaknifemaker and plan to use every inch of it for my platten, has anyone else ever made one this big? I was wondering if I might run into tracking or tension issues with it.