Transportable machining unit, structure and stack arrangement

Transportable machining unit for machining a workpiece with a tool, comprising a box-shaped support structure which can be placed on a support and which has a workpiece support plate which can be used to support the workpiece to be machined, and a drive unit for mechanically driving the tool, which is arranged at least partially in the support structure and is fastened thereto ready for operation, so that the drive unit remains at least partially in the support structure during machining of the workpiece by the tool driven by the drive unit, wherein the support structure has support arms which, in a state, in which the support structure is placed on the support, define a footprint of the support structure, and which can be positioned selectively in a transport position or in a working position, wherein the footprint of the support structure is larger in the working position in at least one horizontal direction than in the transport position.