® Mill-Thread Technical Section Spiral Mill-Thread Inserts Speed and Feed Selection MT7 Sub-Micron Grade with Titanium Aluminum Nitride multi-layer coating (ISO K10 - K20). This is a general purpose grade, which can be used with all materials; it should be run at medium to high cutting speeds. ISO Materials Cutting Speed m/minMT7 Low and Medium Carbon Steels 145 - 360 P High Carbon Steels 165 - 255 Alloy Steels, Treated Steels 135 - 230 M Stainless SteelsCast Steels 165 - 245190 - 245 K Cast Iron 100 - 220 N Non-Ferrous & AluminumSynthetics, Duroplastics, Thermoplastics 230 - 440145 - 590 S Nickel Alloys, Titanium Alloys 30 - 115 Recommended FEED RATE: 0.05 - 0.15 mm As you may note, cutting speed is shown in range terms. In most standard cases choosing a speed in the middle of the range would be a good choice for a start. For hard metals reduce cutting speed. Spiral Finish Speed Selection MT7 Sub-Micron Grade with Titanium Aluminum Nitride multi-layer coating (ISO K10 - K20). This is a general purpose grade, which can be used with all materials; it should be run at medium to high cutting speeds. ISO Materials Cutting Speed (m/min)MT7 Low and Medium Carbon Steels 200 - 330 P High Carbon Steels 170 - 235 Alloy Steels, Treated Steels 100 - 195 M Stainless SteelsCast Steels 180 - 230180 -230 K Cast Iron 200 - 350 N Non-Ferrous and AluminumSynthetics, Duroplastics, Thermoplastics 500 - 1100400 - 1500 S Nickel Alloys, Titanium Alloys 30 - 55 B12-7