Once again, we were able to demonstrate the advantages of our innovative systems in operation at LÄPPLE Automotive.
Once again, we used one of our mobile CNC machining systems for the modification of a sheet metal part of a new car model.
The task was to change the cutting contour of two structural parts by 3mm, i.e. 3mm less material would be cut off the sheets. The width of the changed area was approx. 30mm. It was necessary to adapt several sections of the transfer tool, which weighs a total of 35t, for this modification of a cutting tool. These were two areas each in the lower part, upper part and blank holder. The hardened cutting edges had to be milled in the upper part, which weighs 15t. Material first had to be welded on and then milled to obtain the correct geometry in the lower part and blank holder.
In this use-case, we successfully performed the milling of material with a hardness of up to 63HRC. However, the main challenge during the modification of cutting tools is the accuracy requirement. The cutting edges of the upper tool half must of course enter the cutting inserts of the lower tool without collision. A constant cutting clearance of 0.1 mm along the profile is necessary to cut the sheet properly.
To ensure that several interlocking parts can be machined separately from each other, we use state-of-the-art optical and tactile measuring equipment in addition to our mobile, precise Picum machining tools. We combine first class measuring and CAM software with in-house design of the geometric changes to place modification sections accurately on tool segments and plan machining efficiently. This way, we manage to guarantee the required accuracy and quality with the high-precision-mobile 5-axis-kinematics and reduce follow up manual surface finishing to a minimum.
Picum was again much more time- and cost-efficient compared to the conventional procedure for the use case of a cutting tool modification as described above. In concrete terms, we reduced the time of the modification process up to 52% and realised cost savings up to 65%. In addition, on-site processing prevented CO2 emissions of almost 2 metric tons by avoiding truck transports.