A clamp bench for key duplicating machines, comprising: a fixed component, a first rotary component, a second rotary component and a slide base, wherein the fixed component comprises a first fixed component and a second fixed component, the first fixed component is used to hold a master key in place and the second fixed component is used to hold a key blank in place, wherein the first rotary component, the first fixed component and the second fixed component are rigidly connected to the first plane of the first rotary component, the second rotary component forms a rotary connection with the second plane of the first rotary component, and the second plane and the first plane are opposite to one another, wherein the first rotary component rotates in the axial direction around a first connecting point with the second rotary component, the slide base forms a rotary connection with the second rotary component, the second rotary component rotates in the axial direction around a second connecting point with the slide base, wherein the axial direction in which the second rotary component rotates is the same as that of the first rotary component, characterised in that the second rotary component slides along the slide base, and in that between the first rotary component and the second rotary component a control mechanism is fitted, wherein the control mechanism comprises a cylindrical pin, a control base and a control axis, wherein the cylindrical pin and the control base form a rotary connection, one end of the control axis and the control base form a rotary connection, wherein the cylindrical pin and the second plane of the first rotary component form a fixed connection, the other end of the control axis forms a rotary connection with the second rotary component; the control axis is used to control the movement of the control base and further drive the axial rotation of the first rotary component around a rotary axis. a fixed component, a first rotary component, a second rotary component and a slide base, wherein the fixed component comprises a first fixed component and a second fixed component, the first fixed component is used to hold a master key in place and the second fixed component is used to hold a key blank in place, wherein the first rotary component, the first fixed component and the second fixed component are rigidly connected to the first plane of the first rotary component, the second rotary component forms a rotary connection with the second plane of the first rotary component, and the second plane and the first plane are opposite to one another, wherein the first rotary component rotates in the axial direction around a first connecting point with the second rotary component, the slide base forms a rotary connection with the second rotary component, the second rotary component rotates in the axial direction around a second connecting point with the slide base, wherein the axial direction in which the second rotary component rotates is the same as that of the first rotary component, characterised in that the first rotary component, the first fixed component and the second fixed component are rigidly connected to the first plane of the first rotary component, the second rotary component forms a rotary connection with the second plane of the first rotary component, and the second plane and the first plane are opposite to one another, wherein the first rotary component rotates in the axial direction around a first connecting point with the second rotary component, the slide base forms a rotary connection with the second rotary component, the second rotary component rotates in the axial direction around a second connecting point with the slide base, wherein the axial direction in which the second rotary component rotates is the same as that of the first rotary component, characterised in that the second rotary component slides along the slide base, and in that between the first rotary component and the second rotary component a control mechanism is fitted, wherein the control mechanism comprises a cylindrical pin, a control base and a control axis, wherein the cylindrical pin and the control base form a rotary connection, one end of the control axis and the control base form a rotary connection, wherein the cylindrical pin and the second plane of the first rotary component form a fixed connection, the other end of the control axis forms a rotary connection with the second rotary component; the control axis is used to control the movement of the control base and further drive the axial rotation of the first rotary component around a rotary axis. between the first rotary component and the second rotary component a control mechanism is fitted, wherein the control mechanism comprises a cylindrical pin, a control base and a control axis, wherein the cylindrical pin and the control base form a rotary connection, one end of the control axis and the control base form a rotary connection, wherein the cylindrical pin and the second plane of the first rotary component form a fixed connection, the other end of the control axis forms a rotary connection with the second rotary component; the control axis is used to control the movement of the control base and further drive the axial rotation of the first rotary component around a rotary axis.