Mold project engineers are tasked with designing, building, and qualifying new plastic injection molds so that the molding company can start producing a new injection molded component or product. Understanding the dimensional inspection data produced by the quality team is at the core of this process. Any items listed as out-of-tolerance on the FAIR (first article inspection report) must be adjusted so that the molded part, when cooled, is to print.
There is one factor that often creates headaches for mold project engineers in this process: plastic resin shrinkage.
The Plastic Resin Shrinkage Problem
Plastic resin shrinks and warps as it cools. Chemtech conducts computer warpage simulations at the beginning of every new project. Even with the help of these computer simulations, movement is not always predictable. Figuring out exactly what steel changes are required in the mold tool to get the molded part to print can keep a mold project engineer up at night. To combat this, Chemtech conducts computer warpage simulations at the beginning of every new project. Even with the help of these computer simulations, movement is not always predictable.
Up until recently, the surface profile GD&T (geometric dimensioning and tolerancing) symbol was a cause for concern for most mold project engineers. The issue wasn’t understanding what the symbol means, but how to quickly interpret the dimensional reports created by CMM (coordinate measuring machine) data. Traditional methods like CMMs rely on single-point data collection, making it difficult and time-consuming to pinpoint exactly where a molded part is out of tolerance.
That’s especially frustrating when trying to account for plastic resin shrinkage. Interpreting inspection reports and adjusting tooling has often been more of an art than a science. The challenge comes when the tool engineer must determine what part of the surface is out-of-tolerance. The engineer knows the part is not to print but lacks an understanding of what portion of the parts surface must be adjusted to bring the molded part into print specification. Without extensive point cloud mapping from CMM, understanding the exact location on a surface that requires adjustment is a tremendous challenge.
A New Solution: Blue Light Scanning
With Blue Light 3D Scanning, we can now generate a high-resolution, full-surface scan of your molded part and instantly compare it to the original CAD model. Our advanced evaluation software highlights surface deviations in real time using color maps, allowing our engineers to clearly identify which areas are in-spec — and which need correction. Furthermore, with clear visual feedback, we can communicate directly with mold makers to make targeted steel modifications, reducing the cycle of trial and error.
- Full 360° Surface Analysis
- Fast, Accurate Feedback
- Specific feature isolating capability determines precise dimensional values
- Smarter tool adjustments
How Blue Light Scanning Works, Featuring the ZEISS ATOS Q
Blue light scanning technology recognizes contour by triangulating the angle between a projected fringe pattern and dual cameras, creating a full 3D model of the scanned object. At Chemtech Plastics, we utilize the ZEISS ATOS Q, a powerful industrial-grade blue light scanner that delivers up to 12 million points per scan, features a 3D point spacing of 0.02 mm, and provides repeatable precision up to 6 microns — ideal for capturing complex, high-detail geometries. The part is placed on a high-precision rotary stage and scanned through a full 360°, with some scans performed twice to produce a complete spherical model. This photogrammetric approach enables rapid, ultra-accurate part inspection, which dramatically improves surface analysis, mold corrections, and qualification speed.
Blue Light Scanning at Chemtech Plastics
Chemtech Plastics is proud to be on the leading edge of this technology. We use blue light scanning to help reduce lead time for molds with three-dimensional, curvy surface areas. Contact us today with your next tooling project, and we will show you how to reduce mold qualification time.
