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Best results for drill bit hardness chart
Migiwata Metric M35 Grade HSS-CO 4.5mm Twist Drill Bit Set of 10pcs – Jobber Length, Fully Ground and Straight Shank – 5% Cobalt Added and Extremely Heat Resistant -Drilling Stainless Steel and Iron
Amazon.com
Last update was on: March 31, 2025 9:58 am
- COBALT STEEL - Manufactured from M35 grade cobalt steel, with molybdenum and cobalt added to creates a hardened alloy, measuring Rockwell hardness up to 67, for much faster cutting and extra longer life span, with up to twelve times when compared with an average HSS drill bit.
- FOR STAINLESS STEEL - Particularly successful in cutting through hard metals such as stainless steel and cast iron, although they can be used for softer materials, too. Not for heat treated steel / hardened steel / high carbon steel. Try to adjust the RPM when it fails to penetrate according to our suggested RPM chart.
Migiwata Metric M35 Grade HSS-CO 3.5mm Twist Drill Bit Set of 10pcs – Jobber Length, Fully Ground and Straight Shank – 5% Cobalt Added and Extremely Heat Resistant – Drilling Stainless Steel and Iron
Amazon.com
Last update was on: March 31, 2025 9:58 am
- COBALT STEEL - Manufactured from M35 grade cobalt steel, with molybdenum and cobalt added to creates a hardened alloy, measuring Rockwell hardness up to 67, for much faster cutting and extra longer life span, with up to twelve times when compared with an average HSS drill bit.
- FOR STAINLESS STEEL - Particularly successful in cutting through hard metals such as stainless steel and cast iron, although they can be used for softer materials, too. Not for heat treated steel / hardened steel / high carbon steel. Try to adjust the RPM when it fails to penetrate according to our suggested RPM chart.
