What is the recommended included angle for a drill used when drilling stainless steel?

The recommended included angle for a drill used when drilling stainless steel is typically 140 degrees. This angle is optimal for effectively cutting through the material which is known for its toughness and work-hardening properties.

A wider angle, such as 140 degrees, enhances the cutting edge by providing better clearance and reducing the risk of the drill bit binding in the material. It allows for improved chip removal, which is crucial when working with stainless steel due to its tendency to produce long, stringy chips that can clog the flutes of the drill.

Using a drill with too narrow of an angle may not provide enough cutting edge relief, leading to increased friction and heat generation, which can compromise both the drill bit and the workpiece. Thus, 140 degrees is specifically suited for maintaining efficiency and prolonging tool life when drilling into stainless steel.