M MIMHOOY 3/16" Cobalt Drill Bit Set (10 Pcs), M35 Cobalt Twist Metal Drill Bits for Stainless Steel and Hard Metal

Mimhooy 3/16" Cobalt Drill Bit Set (10 Pcs), M35 Cobalt Twist Metal Drill Bits for Stainless Steel and Hard Metal Specifications: Material: M35 5% Cobalt HSS Angle Point: 135 Degree Manufacturing Process: Fully Ground Measurement System: Inch Flute Type: Spiral T Shank Type: Straight Shank Package Included: 10 pcs x 3/16 inch Cobalt Drill Bit Set Main Features: 1. Self-centering split point allows you to drill directly to the size needed without any pre-drilling. 2. Fully Ground spiral groove design clears particles quickly, decreases friction and heat for a faster and cooler drilling performance. 3. M35 Grade Cobalt Steel: This drill bit contains 5% Cobalt (M35 Cobalt HSS), which increases the strength, the tool life and makes it more heat-resistant. Rockwell Hardness >= 67. 4. M35 Cobalt HSS is more suitable for hardened material. Particularly successful in cutting through hard metals such as stainless steel, cast iron, high temperature alloy. 5. 135 degree means less force required to remove metal, compared with lower angles like 90° and 118°. ATTENTION: 1. Keep the drill bit vertical with the stuff's surface to be drilled. Non-vertical use may cause the drill bit to break. 2. Using cooling liquid will make the bit last longer. Suggest to keep the bit cool during drilling, otherwise, the bit may easy to melt. If not have the cooling liquid can use the water instead. 3. Drilling metal requires low RPM. The bigger diamater brill bit, the lower RPM. The harder material, the lower RPM. Details for RPM: If drill diameter ?5mm, RPM(1000~700) If Drill diameter 5-10mm, RPM?700~350? If Drill diamete10-15mm, RPM?350~200?