A portable machining apparatus facilitates addition of new electric components with an intended arrangement of various electric components. The portable machining apparatus includes a housing, an electric motor installed in the housing and including a motor shaft extending in an axial direction, a tip tool partially or fully exposed outside the housing and rotatable by the electric motor, a controller installed in the housing and aligned with the electric motor in the axial direction to control an operation of the electric motor, and a first electric component and a second electric component installed in an electric component compartment between the controller and the electric motor. The first electric component and the second electric component are aligned in a same plane perpendicular to an axis of the motor shaft.

A power tool having at least one front handle and a tool, wherein the tool can be cooled with a cooling liquid during the operation of the power tool. The power tool has a regulating unit for providing the cooling liquid, wherein the regulating unit has a valve for setting a quantity of cooling liquid and is integrated on the front handle.

A power tool having at least one front handle and a tool, wherein the tool can be cooled with a cooling liquid during the operation of the power tool. The power tool has a regulating unit for providing the cooling liquid, wherein the regulating unit has a valve for setting a quantity of cooling liquid and is integrated on the front handle.

A tool nut includes a frustoconical nut body that defines a central longitudinal axis of rotation, the frustoconical nut body comprising a top surface that defines a first diameter and a bottom surface that defines a second diameter, the second diameter greater than the first diameter, the bottom surface comprises a contiguous flat surface transverse to the central longitudinal axis of rotation; a threaded passage through the frustoconical nut body along the central longitudinal axis of rotation, the threaded passage operable to thread onto a spindle of a cutting tool; a counterbore in the bottom surface along the central longitudinal axis of rotation; a first mounting feature through the frustoconical nut body along a first axis parallel to the central longitudinal axis of rotation; and a second mounting feature through the frustoconical nut body along a second axis parallel to the central longitudinal axis of rotation, the central longitudinal axis of rotation, the first axis, and the second axis, along a common line.