To put it simply, the coating is like the clothes of an end mill.
In different occasions, it needs to be worn the right clothes. For example, people need to wear a spacesuit when they are in outer space, and a swimsuit when they swim. Therefore, depending on your processing conditions, it will affect what coating you need to choose.
To realize the longer tool life and the stable cutting with minimum wear, Speed Tiger Flat Bottom Drills are designed for drilling angled or wavy surfaces, cross holes or eccentric hole, and thin or stacked plates, or for simply creating a flat bottom hole. The following graphic expression will help you understand at a glance.