Non-contact 3-D laser scanning captures everything on the surface of the objects, including free-form shapes and fine details. The technology works by projecting a line of laser light onto a surface while cameras continuously triangulate the changing distance and profile of the laser line as it sweeps along. The laser line passes back and forth over the area until the complete surface is captured. Irregular shapes are measured just as easily as prismatic ones, and they are instantaneously replicated digitally on-screen.

The scanner measures very quickly, picking up tens of thousands of points per second, and generates huge numbers of data coordinates in a point cloud. Several scans are made to capture the entire part and then the point cloud data files are rotated into the same reference frame and assembled into an exact 360-degree representation of the scanned part.

Since laser scanning is a non-contact measuring method, there are no variations in practices or techniques from operator to operator, or pressure differences that may generate different readings in traditional touch-probe measurement. Laser scanning allows extremely consistent capturing of parts’ geometry by removing the human error factor.

The point cloud data was compared directly to the molds’ CAD to verify their acceptability. A color-coded inspection report was quickly generated that provided more information about the mold’s acceptability and to find discrepant areas. The gradations of color show the extent to which the area is out of tolerance when compared to the CAD model: areas that are larger than spec appear in yellows and reds; areas smaller appear in blues and purples.

The scan data showed that the physical molds were not identical to the CAD model. However, once the discrepant items were looked at in more detail, there were only a few insignificant errors among them.

Based on the scan data, the moldmaker could quickly be certain that the new refurbished mold met the criteria of the 2-D drawing and the acceptable standards.
The digital scan data also allowed the moldmaker to correct the CAD model, so that it matched all the dimensions of the drawing. Future inspections will be fast and efficient because the scanning setup is saved as a template so when the same part is inspected, it is immediately available. Molds can be qualified in just hours and at regular intervals by laser scanning inspection techniques.

Not only did the customer save time with 3-D scanning, they also saved over half the cost of manual measurement.