This is our Parker Liberty One CNC cylindrical grinder, modified with our oil-hydrostatic tailstock and wheel-head. Parker grinders are made in Pennsylvania by Penn United. In this video we are grinding a shaft for an air bearing spindle that is used for writing tracks on hard disks. We made the tailstock with a hydrostatic bearing because we don't want to have it wear and develop lost motion. The wheel spindle, one of our hydrostatic 4R Blockhead spindles, is belt driven by the original motor. We are holding 1/4 micron roundness, straightness and size on hardcoated aluminum with this machine.
1/4 micron is impressive!
ghull1 1 week ago