It's past time that I change my jointer knives. It's a 6 in. Jet and I would like to remove all 3 knives at once and take them to my local saw shop to get them sharpened. Searching the web I find a site that says removing all knives will "stress" the clutter head and a site that says remove all three knives at once. I know I can purchase new knives cheaply and change them one at a time, but I like my local saw shop. Does anyone know if it's ok to remove them all? Has anyone ever stressed a cutter head? Am stressing to much?