STROTON M42 8％ Cobalt Twist Drill Bits (11mm x 2PCSfor Stainless Steel and Hard Metal.

Product Advantages : (1 3 Steps desigh tip starts drilling immediately with less force and eliminates walking across the work surface. (2Holds up better than generic highspeed steel, Cobalt gives highspeed steel more heat and wear resistance. (3This drill bits set is made of Premium Cobalt (80,000 dollars per ton. (4The M42 metric cobalt drill bits can cut through Stainless steel and Hard metal,Hard wood, although they can be used for softer materials such as Aluminum,Plastic. Some Important Tips about drilling stainless steel and hard metal : (1Controling the drill speed from 200 to 1000 RPM would make it easier for you to drill holes on stainless steel. Stainless SteelDrill diameter RPM≤5mm 1000~700510mm 700~3501015mm 350~200(2Add stainless steel tapping oil or engine oil to prevent the stainless steel from overheating and forming a very hard oxide layer. It also works adding some vinegar,soy sauce or water if you dont have engine oil.