BB Step Drill 90 Degree 180 CNC Precision Solid Carbide Drilling Tools DLC Coated Screw Hole Hole Diameter:5.0x6xD8x10x60 so it is not necessary

so it is not necessary to achieve a high drilling rate

But it also makes it easier to break

using special steel lattice mixed processing

full cutting should be avoided as much as possible

Fully Ground Cutting Edge Smooth Cutting Wear-Resistant and Durable

BB Step Drill 90 Degree 180 CNC Precision Solid Carbide Drilling Tools DLC Coated Screw Hole Hole Diameter:5.0x6xD8x10x60 so it is not necessaryExample 1x5xD4x10x50 d=1mm, L1=5mm,D2=4mm,L2=10mm,Overall Length=50mm Once Formed Drilling+Chamfering The blade edge is sharp without burrs, easy chamfering Greatly improves work efficiency. Solid Carbide Bars High Hardness High Wear Resistance A specialized tool for high hardness and high speed cutting applications with higher wear resistance and strength Nano Diamond Coating Enhance tool hardness and service life, improve machine tool productivity,