Friction Saws blades are designed for cutting sections of mild steel. Sawing of ferrous metal with this type of blade is done by friction which requires a fine tooth blade, operated at high arbor speed, these frictions saws are used for heavy duty cutting operations. Since friction blades actually burn through the stock, removing globules of metal rather than chips; some burring of the material may result. However, friction saws are superior to abrasive wheels where finish and cutting life are important. To avoid damaged blades and excessive burring, it is recommended that friction saw blades be changed frequently for sharpening. Friction saw blades are always inspected for flatness, tension, balance and cracks, on both new blades and when serviced.