Improving Internal Turning In A Blind Hole

Haven't posted lately, but today have time for a quick tip or two.

It doesn't matter if your using carbide inserts, ceramic inserts, or CBN Inserts, internal turning in a blind hole brings about the problem of chip evacuation. When the cutting tool reaches the rear side wall, chips may be caught between the wall and the insert. This may cause the insert to break.

Here are two solutions I found from a carbide insert manufacturer that can eliminate cutting tool breakage:

First Solution
1. Start by grooving at the rear wall.
2. Continue by turning from the inside toward the outside.

Second Solution
Start by grooving at the rear wall. Pull the tool back to the outside. Turn the final diameter from outside toward the groove.