Abstract: A machine for pre-adjusting and balancing a tool-holder, includes a support frame provided with a single rotary tool spindle, a column supporting a dimension-measuring arm, a console displaying the measurements and a protective hood preventing access to a risk area when the spindle is rotating.

Abstract: A tool presetting device comprises a carrier device for rotatably holding a tool. The tool is received in a bearing bushing which defines a bearing axis and provides a rotationally symmetrical bearing surface wherein said tool is enabled to be rotated in a desired measuring and setting position. An air suspension can be built up for enabling rotation of the tool. To this end, a source of pressurized air is provided which enables a certain throughput of air. At least one air outlet opens at the bearing surface, while receiving pressurized air from the said source. A switching device either admits or prohibits access of pressurized air to the air outlet. A throttle valve is connected to the source of pressurized air for limiting the throughput of air.