GLOBAL STATUS Gives Die And Mold Maker Capacity, Speed And Accuracy To Handle More Work
Mattson Tool & Die is an ISO 9001 registered die and mold maker that manufactures precision plastic injection molds, trim dies and vacuum form dies for the automotive industry. The company offers broad processing capabilities including CAD/CAM, CNC machining, CNC wire EDM and CNC die sinking machines with capacities up to 6.5 feet x 13.5 feet, backed up by a sophisticated inspection operation.
At Mattson Tool & Die, the GLOBAL STATUS CMM is used in a quality control/quality assurance role to verify that the dimensions of the machined molds and dies meet tolerances on the CAD drawings supplied by customers.
"We often use the machine for in-process inspection, too," said Mark See, Mattson CMM Operator. "For example, I've just checked a mold that hasn't had the leader pin and bushing holes machined in it yet, but the die-leader wants to verify that the shape meets specifications before the holes are put in."
Large Volume Expands Capacity
Mattson Tool & Die machines a wide range of part sizes, from workpieces that are about two inches square to dies and molds that weigh up to 40,000 pounds.
"I've had the table of the GLOBAL full, with almost the entire working area of the three axes taken up with a workpiece," See said. "In fact, the reason we purchased the GLOBAL STATUS was to handle larger workpieces."
Mattson Tool & Die selected a GLOBAL STATUS 12-22-10 with a 1,200 mm X 2,200 mm X 1,000 mm measuring volume. It is installed in an environmentally controlled room located near the center of the CNC department. The room is unique in that is has a large, retractable door as a ceiling. Massive workpieces can be moved by overhead crane directly over the GLOBAL STATUS and lowered to the CMM's table. One end of the room is fitted with doors for the delivery of smaller workpieces.
A typical inspection routine takes about an hour and a half—two hours to verify the dimensions of a cover and an ejector half. Generally, 50 to 200 points are collected per workpiece, measuring to tolerances of 50 to 100 micrometers.
The company produces such a broad spectrum of parts that pre-programming of measurement routines isn't efficient. Nearly each workpiece requires it own inspection routine. In order to facilitate workpiece alignment on the CMM, See has developed a Visual Basic program that helps operators, by means of prompts, align each mold prior to the inspection cycle.
"Once the part is loaded, I'll import the CAD model, perform an alignment using the tooling holes and then check the areas that the die-leader or customer wants to verify," See said. "I'll find the approximate points on the workpiece and then do vector, surface or edge points to verify positions."
The GLOBAL STATUS has an ISO 10360-2 accuracy for touch probes of 3.9 + L/250. TRICISION™ bridge design provides optimum stiffness-to-mass ratio with a lower center of gravity and a wider bearing separation than competitive bridge designs to improve overall machine accuracy. Continuous axes motion interpolation and true 3D vector capability (FLY) integrates axes movements by eliminating stops and corners for more precise data collection and improved machine throughput to help reduce overall inspection time.
Gathering Data by Scanning
In addition to its capability to measure prismatic features and position, the GLOBAL STATUS can also be used to scan contours and free form surfaces—important for reverse engineering applications.
"We're doing more and more reverse engineering," See said. "Often we get molds that have no CAD models. We scan the shape with the GLOBAL STATUS using the PH10M and use the data to create a CAD representation of the mold."
The company also performs third party fixture certification and reverse engineering services for local companies.
"In some cases we've had to scan actual parts to help our customer determine where a particular mold fit problem is located," See said. "Our customers use the dimensional data in conjunction with their CAD program to fine tune the mold."
GLOBAL Point, Click and Scan Technology™ combines and optimizes temperature and accuracy compensation systems, motion controllers and advanced algorithms to support high-speed, high-accuracy analog open and closed loop scanning applications. This advanced technology facilitates high speed scanning by automatically generating scan and probe paths and inserting moves to avoid obstacles.
The special Object Oriented Scanning feature allows the controller to define the scan path from only a single user command. Exclusive 3D Vector Force Optimization (3D VFO™) performs a 3D force vector analysis at every probe qualification assuring continuous, accurate probe compensation and improved data analysis in all scanning applications. GLOBAL's probing technology feature allows a scanning probe to be used as a touch trigger probe with no loss of speed or accuracy.
PC-DMIS version 3.25, when released, will be an aid in the company's third party fixture certification program, according to See.
"This version of PC-DMIS has an auto-feature cone. With fixture certifications, a lot of four-way and two-way locators are cones, and having the auto-feature capability makes the entire certification process easier and, I think, more accurate," he said.
See added that he extends the capabilities of PC-DMIS using Visual Basic programming. "For example, I'll use Visual Basic in conjunction with PC-DMIS to create custom reports using Microsoft Word and Excel."
The GLOBAL STATUS, combined with Mattson's other inspection systems, is helping the company build on its reputation for high quality die and mold making. "We are continually looking for new ways to use the CMM and the software to enhance our capabilities for our customers," See added.
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