Clamping cones, SP The clamping cones are connecting members between a shaft, e.g. an engine shaft or a spindle shaft, and a drive shaft. The clamping cone consists of two parts and makes it possible to connect a cylindrical shaft with a conical bore in the drive shaft. No special machining of the shaft is considered necessary. The drive shaft bore must be machined conically, which really only makes proper sense with large piece numbers.