5 Axis CNC Machining: VMT 5 Axis CNC Machining Manufacturer Explains to You about RTCP

The RTCP (Rotary Tool Center Point) function maintains a constant angle of the axis of rotation between the tool and the surface of the part being machined. Machines also allow OEMs to build functionality based on the mechanical characteristics of the user's machine. The RTCP function automatically manages the offset of all irregular shapes and maintains tool contact with programmed points. It uses the contact point as a reference point in all calculations, allowing the user to program the machine directly with CNC machining the part contour and the desired tool angle.

RTCP, in the high-end 5 axis CNC machining system, considers RTCP as the center point of the rotating tool, which is what we usually call the tool nose point tracking function. In 5 axis CNC machining, when the trajectory of the tool head point and the attitude between the tool and the CNC machined part are tracked, the rotary motion will generate additional motion of the tool cusp.

The control point of the CNC system often does not coincide with the tool tip. Therefore, the CNC system must automatically correct the control points to ensure that the tool nose point moves according to the commanded predetermined trajectory. The industry also has such a feature called TCPM, TCPC or RPCP. In fact, the functional definitions of these names are similar to RTCP.

In a strict sense, the double swing head structure uses the RTCP function to compensate with the center point of the swing head. The RPCP function is mainly used in machine tools in the form of double turntables, and the compensation is the change in the coordinates of the linear axis caused by the rotation of CNC machining parts. In fact, these functions are the same to keep the tool and CNC machined part surface unchanged between the tool center point and the actual point of contact. Therefore, for the convenience of description, this paper unifies this technology as RTCP technology.

Application of RTCP in 5 axis CNC Machining Center

The rotary tool center point, also known as TCPM, TCPC or RPCP, refers to the function of maintaining the equiangular rotation axis of the tool and the surface of the machined part. In 5 axis machining, when tracking the trajectory of the tool point and the angle between the tool and the CNC machined part, the additional motion of the tool point is generated due to the rotational motion. The control points of the CNC system often do not coincide with the tool points, so the CNC system should automatically correct the control points to ensure that the tool points move according to the given trajectory.
 

So how is the RTCP function generated? Many years ago, 5 axis CNC machining machines were just popularized in the market, and the RTCP concept was widely publicized by machine tool manufacturers. At the time, the RTCP feature was more of a gimmick for technology and technology. More and more people are enthusiastic and enthusiastic about the technology itself.

In fact, the RTCP function is just the opposite, it is not only a good technology, but a good technology that can bring benefits and create value to customers. The machine tool adopts RTCP technology (also known as real 5 axis CNC machining machine in China), the operator does not have to align the workpiece precisely with the axis of the turntable, and the machine tool automatically compensates for the offset, which greatly shortens the auxiliary time and improves the quality of CNC machining . accurate. At the same time, as long as the coordinates and vectors of the tool tip are output, post-processing is very simple. As mentioned earlier, in terms of mechanical structure, 5 axis CNC machining machines mainly include double shaking heads, double turntables, swings and turns.

For 5 axis CNC machining machine tools and CNC systems without RTCP, how to solve the problem of linear axis coordinate offset? We know that many 5 axis CNC machining machines and systems in China are fake 5 axis. The so-called fake 5 axis is actually a machine tool without RTCP function. The real and fake 5 axis CNC machining machine, neither look at nor look at five Whether the axis CNC machining is connected together.

It is necessary to know that the 5 axis CNC machining can also be connected by five axes. The main difference between the pseudo-5 axis CNC machining machine is that it does not have a real 5 axis RTCP algorithm, that is, pseudo-5 axis programming needs to consider the spindle Swing length and turntable position. This means that when programming with fake 5 axis CNC machining systems and machine tools, CAM programming and post-processing techniques must be relied on to pre-plan tool paths.

The pseudo-5 axis CNC machine tool is based on post-processing technology, which displays the positional relationship between the fourth and fifth axes of the machine tool to compensate for the displacement of the rotation axis to the linear axis coordinates. The generated NC programs X, Y and Z are not only the programming method points, but also include the necessary compensations for the X, Y and Z axes. The result of this kind of CNC machining not only leads to low CNC machining accuracy, low efficiency, and poor generality of the generated programs, but also requires high labor costs.

At the same time, due to the different rotation parameters of each machine tool, there must be corresponding post-processing files, which will bring great inconvenience to production. In addition, the program generated by the pseudo 5 axis CNC machining machine cannot be changed, and it is basically impossible to realize manual 5 axis CNC machining programming.

At the same time, because there is no RTCP function, many 5 axis advanced functions cannot be used, such as the 5 axis tool compensation function. In fact, for a 5 axis CNC machining machine, it is just a tool to achieve the processing effect, and there is no true or false point. Importantly, our process determines how it is handled. Relatively speaking, a true 5 axis CNC machine is more cost-effective.