5-Axis machining of curved surfaces

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The Canadian tool, die and mold making industry has gone through a tumultuous period. From sales of $1.2 billion in 2002 it dropped by 40+% in the ensuing decade as manufacturing moved offshore in search for lower labor cost. Rising wages and transportation cost have eroded the advantage and the Canadian market is once again on a growth trend. By 2026, Thomas Insights, predicts the machining market will grow by 5.5% annually and reach $128 billion worldwide. The growth is fuelled by novel ways of machining to reduce production cost and increase productivity. The applicant's research has made a transforming leap that will help machining of precision dies and molds by reducing finish machining time by up to 70%. The development of a sound theoretical foundation that results in a robust, simple, and fast 5--axis based Multi-Point Machining (MPM) method for machining curved surfaces, has opened the door for the proposed research program on machining surfaces typically found in tool, die and molds. The flexibility of 5-axis machines is used to place the tool near the surface and machine a wide strip along the toolpath, where tolerance criterion is satisfied. The method is best explained as dropping the tool, onto the closet point on the surface, followed by tilting, to the nearest point, without losing contact at the first point. This Drop Tilt Method (DTM) has received great attention in academic circles. The current proposal addresses additional challenges that will open the path for the DTM to be adopted into industry. The main challenge in the research program stems from the need to control the width of the machined strip and to control the tilt of the tool axis. The width control ensures that the finished surface is divided into tolerance zones reducing the possibility of over or under material removal in the subsequent tedious and time-consuming operation of hand polishing. Similarly, an optimized tilt will help reduce machining time. Work has already started along the sample strategy outlined above. The preliminary investigation has been successful and will be pursued to completion under this proposal. The success of the strategy will further the goal of advancing the understanding of Multi-Point Machining research program to a level where it can be successfully adopted by industry. The application of MPM beyond machining to fields such as grinding remain open research domains. The students conducting the research will gain expertise in foundational knowledge and in practical skills. They build s strong base in machining, numerical methods, experiment design, validation, and research design and learn to use machines and tools encountered in machining labs. This expertise will be required when solving industry problems during their careers in machining, aerospace, automotive, tool and die industries among others.