Name for a tool interface with hollow taper shank, which is standardized according to DIN 69893.
Hollow shaft taper are about 30% smaller and about 50% lighter than steep-angle tapers. However, because of their construction they have an even higher rigidity and because of the optimal support surfaces, a higher positioning accuracy in the machine feed. Hollow shaft tapers are suitable for higher speeds, since with an increasing of the centrifugal force, the clamping force is also increased.
The tool interface HSK-F50 was introduced in wood working in the 1990s. Since in some situations, the tension forces proved to be too low, it was successively replaced by the standard HSK-F63 since the end of the 1990s.