For moldmakers using multi-axis machine tools, developing CNC programs that can give full play to the capabilities of these machine tools is a difficult problem. Its purpose is to make full use of the movement of the additional axis of the machine tool (workbench or tool holder) in the most effective way, and at the same time make the mold have a good surface finish.
In recent years, the synchronous movement of machine tools has become more and more complicated, which also makes the CAM software system face difficult problems in both mathematics and technology. The rapid development of processing technology has made it difficult to synchronize the development of high-efficiency CNC programs that can be used to run machine tools.
In addition, software products designed for multi-axis machine tools must be easy to use and correct. Because the materials, high-precision tools, and accessories used in these advanced machine tools are very expensive, even the smallest programming errors can cause significant losses.
Based on these premises, the problem faced by CAM software developers is how to combine these powerful programming functions with a programming process that is easy to understand by users. These functions must be clearly stated in order to guide the user through the programming process, so as to avoid errors in determining the tool path. At the same time, it will not make the programming process rigid or restrictive.
In order to provide users with a variety of processing solutions, CAM software developers always decompose four-axis and five-axis processing into various special functions that can be used for various tool paths. In fact, some CAM developers are proud of their ability to provide a variety of specialized functions.
The cost of developing this type of software is to make the function of the system incomprehensible. The typical end user can only understand and utilize limited functions. It is impossible for CNC programmers with busy business to remember the purpose of the many functions of the CAM system, so they usually only program according to the functions they are most familiar with, and ignore other functions.
Four simplified steps
The new concept of advanced machining functions is based on the view that any five-axis machining function (no matter how complicated) can be defined in a few simple steps. The mold manufacturer has adopted a tried and tested method to set up the mold production program:
(1) The area to be processed and the processing sequence. This step is based on the complexity of the shape of the part, and is often the easiest to inspire the inspiration of a skilled mechanic.
(2) What shape should the tool trajectory in the machining area have? Should the tool cut in the order of front and back or up and down according to the parametric lines of the surface, and the surface boundary as a guide?
(3) How to guide the tool axis to match the tool path? This is very important for the quality of the surface finish and whether shorter hard tools are used in a small space. The mold maker needs to fully control the tool, including the fore and aft inclination when the tool is tilted. In addition, it is necessary to consider the angular limit caused by the rotation of the worktable or tool post of many machine tools. For example, there are limits to the degree of rotation of milling/turning machine tools.
(4) How to convert the cutting path of the tool? How to control the displacement of the tool due to reset or displacement and the displacement that the tool must produce between the machining areas at the starting point of the tool path? The displacement produced by the conversion process is very critical in mold production. It can eliminate the traces of the witness line and the tool (which can be removed by manual polishing afterwards).
Post time: Sep-22-2021