Custom machining of an Ottet collet enables uniform clamping of a thin annular part.

Usually also works very well for non-circular parts.

For optimum repeatability, care must be taken with deburring and attention must be paid to possible radii or chamfers on the finishing cutter if the workpiece to be clamped has a sharp angle on the clamping diameter.

For cylindrical parts, indexing with a pin inserted in the collet is generally the simplest solution.

For collets with top clamping it is also possible to position the NC with a pin in a tool holder (or broken cutter mounted upside down). Place the workpiece on the collet in the NC, press it against the pin and collet.

This method allows more freedom to machine the complete contour of the part. For example, when machining a case middle from a blank or for reworking during the second operation.