TCT Carbide Tipped Knives offer over 1,000% (10 times) the tool life of T1-HSS. Carbide is used _disibledevent= "urn:schemas-microsoft-com:office:smarttags" />Hickory, Hard Maple, MDF, plywood, etc.) Carbide is very hard (~92 Rc)and should be sharpened using a diamond wheel or silicon carbide type grinding wheel (call if you need these grinding wheels). Carbide can wear over 100,000 lineal feet, but is also brittle and can chip if the wood is not free of staples or rocks. We also offer solid carbide knives and Knife-Lock; a two section (carbide & steel backing) Moulder knife set used to profile MDF and other glued up panel type