A drill guide device comprising a speed detection device for measuring speed of a drill bit used by the device for drilling an object surface during a hand drilling operation; a force detection device for measuring force applied by the drill bit on the object during the hand drilling operation; an alignment detection device for detecting alignment of the drill bit with respect to the object surface during the hand drilling operation; a user interface connected to the speed detection device, the force detection device and the alignment detection device adapted to communicate to a user information related to the speed, the force and the alignment of the drill bit during the hand drilling operation. The drill guide device is preferably used for training technicians on hand drilling the object surface using a required range of force, speed and alignment, particularly muscle memory training of technicians on these required parameters.

A control method for the use of a core drilling system including a core drill and a feed device for driving the core drill along a machine holding device, including the following method steps:determining the end of a core drilling operation on the basis of reaching a predetermined threshold value for at least one corresponding predefined drilling parameter; andselecting a reversing mode for retracting a drilling tool out of a borehole at a reversing rotational speed which corresponds to a multiple of a predetermined tapping rotational speed of the drilling tool at the beginning of the core drilling operation. A feed device, a core drill, as well as a core drilling are also provided.

A method for detecting whether a slip clutch release event has taken place in a power tool includes determining a first speed of a gear device by a first sensor, determining a second speed of a motor by a second sensor, and determining a current value by a third sensor. The method further includes determining a state of the power tool by using the first and second speeds and the current value, determining a state of the gear device in dependence on the current value by a control device, ascertaining a state of activity of the slip clutch in dependence on the first and second speeds by the control device, and ascertaining by the control device by a combination of the state of the gear device and the state of activity of the slip clutch whether the slip clutch release event has taken place.

A control method for the use of a core drilling system, including a core drill and a feed device for driving the core drill along a machine holding unit, including the method steps: detecting at least one first drilling parameter value during the core drilling operation; establishing the at least first drilling parameter value as a reference value; detecting at least one second drilling parameter value during the core drilling operation; comparing the at least second core drilling parameter with the reference value; and selecting a predetermined parameter setting for the core drilling system if the second drilling parameter exceeds or falls below the reference value by a predetermined corresponding threshold value. Also a feed device for driving a core drill along a machine holding unit for use of the method, a core drill for use of the method as well as a core drilling system including a core drill and a feed device for driving the core drill along a machine holding unit for use of the method.

A control method for using a core drilling system is disclosed. In an embodiment the method includes detecting a predetermined drilling situation on the basis of the attainment of a predetermined threshold value for at least one predetermined corresponding drilling parameter and ending the core drilling operation by selecting a reverse-travel mode for removing the drilling tool from the borehole if the advancing device does not reach a predetermined threshold value for a predetermined corresponding distance value in a direction and the core drilling machine does not reach a predetermined threshold value for at least one predetermined corresponding drilling parameter or continuing the core drilling operation by selecting a predetermined operating mode if the advancing device reaches a predetermined threshold value for a predetermined corresponding distance value in a direction and the core drilling machine reaches a predetermined threshold value for at least one predetermined corresponding drilling parameter.

A method to control a power tool includes the following steps: ascertaining a first rotational speed of the transmission in a first gear; ascertaining a first rotational speed of the motor when the transmission has been put into a first gear; ascertaining the selection of a first gear on the basis of the ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; selecting the no-load state; ascertaining the selected no-load state on the basis of the ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; adapting the rotational speed of the motor to a second gear on the basis of a ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; and selecting a second gear.

A drill guide device comprising a speed detection device for measuring speed of a drill bit used by the device for drilling an object surface during a hand drilling operation; a force detection device for measuring force applied by the drill bit on the object during the hand drilling operation; an alignment detection device for detecting alignment of the drill bit with respect to the object surface during the hand drilling operation; a user interface connected to the speed detection device, the force detection device and the alignment detection device adapted to communicate to a user information related to the speed, the force and the alignment of the drill bit during the hand drilling operation. The drill guide device is preferably used for training technicians on hand drilling the object surface using a required range of force, speed and alignment, particularly muscle memory training of technicians on these required parameters.

A machine tool is configured to receive input data defining a profile to be machined onto a workpiece, with the profile defined in a plane perpendicular to an axis of rotation of the workpiece and non-circular in that plane, and calculate using an evolutionary algorithm a workpiece velocity profile corresponding to the velocities at which the workpiece is to be rotated by the workpiece mount over at least part of a rotation of the workpiece during machining. The machine tool then rotates the workpiece according to the workpiece velocity profile during machining of the workpiece.

A method to control a power tool includes the following steps: ascertaining a first rotational speed of the transmission in a first gear; ascertaining a first rotational speed of the motor when the transmission has been put into a first gear; ascertaining the selection of a first gear on the basis of the ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; selecting the no-load state; ascertaining the selected no-load state on the basis of the ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; adapting the rotational speed of the motor to a second gear on the basis of a ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; and selecting a second gear.

A material for assisting metal machining process, having a polymer compound, wherein a content of the polymer compound is 50% by mass or more based on the total amount of the material for assisting metal machining process, a melting point is 40 C. or more, and a temperature at 5% weight loss is 275 C. or more.