BB Micro Drill Bit Shank D=4mm BF2055 Corner Radius 5 D8 35 150 4T

5 D8 35  150  4T 8R1 D8 20  60  4T 8R1 D8 25  75  4T 8R1 D8 25  100  4T 8R1 D8 35  150  4T 8R1

5 D6 18  75  4T 5R0

because rotary speed does not affect the cutting speed

3 D4 6  50  4T 3  1R0

BB Micro Drill Bit Shank D=4mm BF2055 Corner Radius 5 D8 35 150 4TBB Mirco Drill 1PCS The whole bit is made of Solid Carbide, which makes the bit more durable. But it also makes it easier to break, so it's forbidden to use electric hand drills and unstable machining environments. Application Steel, stainless steel, cast iron, die steel, circuit board,acrylic and so on. Diameter of shank : 3mm or 4mm Recommended Cutting Conditions *Reference parameters are used as the general standard and need to be adjusted