3D scanning ensures injection mold accuracy

The Mississippi Polymer Institute (MPI)* helps smaller companies in the polymer industry use an NVision MobileScan laser scanning system to re-engineer or inspect parts to a high level of accuracy. “By inspecting first articles, we help injection molders ensure that their first article matches the design intent,” said Bryan Brister of MPI. “We also re-engineer tools and parts to create a CAD file that can be used to reproduce the object or modify its design.”

MPI uses rapid prototyping technology to produce concept models and functional prototypes for clients. “We recognized an unmet need to perform first article inspections and to provide CAD files of parts that were designed using manual methods,” Brister said. “We evaluated lasers from a number of companies and selected the MobileScan laser scanner from NVision because it is the most accurate mobile scanner we could find.”

NVision’s MobileScan 3D laser scanning system provides a point spacing of 0.001 in. and an accuracy of +/- 0.0005 in. while collecting measurements at a rate of 30,000 points per second. The MobileScan HD sensor has a 2-axis servo controlled swivel head integrated with a turntable. The key to the system’s accuracy is that it uses only one servo and rotary encoder at any one time and these components are manufactured to the highest specification available. “By minimizing the opportunities for error to be introduced; the highest level of accuracy can be achieved,” said Steve Kersen, VP of Sales and Marketing for NVision.

One example of an MPI laser scanning project involved a professor from a dental school who wanted to build posts to mount a number of dental crowns for educational purposes. MPI scanned the crowns with the MobileScan and produced a CAD file. Then they made inverse images of the cavities in the crowns and used them to build the post on a rapid prototyping machine.

Nvision 3D scanning researchIn another project, an injection molding shop approached MPI because they had a tool that had cracked but were unable to build another because they did not have a CAD file. MPI scanned the mold, electronically repaired the crack and created a CAD file. The mold shop used the CAD file as the basis for a computer numerical control (CNC) program that was used to build the new mold.

 

NVision Inc.
www.nvision3d.com

*MPI is a resource for polymer-related industries in Mississippi, sharing its expertise in the sciences, computer applications, product design and manufacturing of polymer materials, plastics processors, product designers and manufacturers that use polymer components in their products. It is associated with the School for Polymers and High Performance Materials at the University of Southern Mississippi, recognized as one of the top 10 Polymer Science Programs in the United States by U.S. News and World Report.