RS322 (for high speed oversize through boring) A 3/8” (9.52 mm) IC, square insert with a black ceramic coating. It is used on Rottler boring machines for through boring when removing .010” - .060” (.25 mm - 1.5 mm) on the diameter. A very economical insert as it has 8 cutting edges. On a 4” (100mm) bore use 1000 - 1200 RPM and a feed rate of .008” - .012” (.2 mm - .3 mm) per rev feed rate to obtain the typical surface finish. The insert can also be used for sleeve cuts when a square step is not required. For example, when used on an F80 or F5 machine it can be run at 1000 – 1200 RPM and .005/rev (.12 mm/rev) feed rate to remove up to .200” (5 mm) on the diameter from a 4.200” (106 mm) bore. When cutting nodular, ductile, or compacted graphite cast iron the speed should be in the 200 – 400 S.F.P.M. area – 300 RPM on a 4” (100 mm) diameter bore. Nodular, ductile, or compacted graphite cast iron is found most often in high performance engine blocks or sleeves. When cutting these tuff cast irons it is best to use a feed rate of between .006” and .010” (.15 mm and .25 mm) per revolution.
