What is a wiper insert?

Sandvik Coromant () explained: The wiper technology for turning is based on a carefully developed series of radii that make up the cutting edge. On a conventional insert, the nose of the edge is just one radius. The wiper edge, however, is made up of a large, main radius complemented by several smaller radii. The long wiper edge should not misshape the surface nor generate unacceptable cutting forces. The wiper insert should also be as straightforward to set up and use as an ordinary insert.

In turning with a single-point tool, the surface finish is determined by the feedrate and nose radius, as these are in a direct relationship to the profile height of the surface (Rmax). This means that the higher the feed, the rougher the surface generated by the edge of a given nose radius.

Wiper inserts have changed this through the effect of their specially developed edges that smooth the scalloped tops that would otherwise have been created. An additional important feature is their improved chip-breaking capability. Wiper geometries are also designed to combine good chip control at low feeds and smooth chip breaking at high, productive feeds.