Issue link: https://iconnect007.uberflip.com/i/746712
74 The PCB Magazine • November 2016 also involve an explanation of how the system shows that the interlocks are defeated—indicat- ing dangerous Class 4 system status, rather than safe Class 1 operation. Furthermore, system startup and shutdown should be covered, including how to put the laser into standby mode and understanding the time required for the laser to warm up and stabilize after re- turning from standby. A review of the operator interface—how to log in, how to initialize the system, and process panels, how to start and stop jobs, and other production features—will similarly be covered in a typical training. Beyond operator training, assuming you will not exclusively use the system for a single appli- cation for the life of the tool and have already been given the production process for that ap- plication, it is important to train your process engineer or process engineering team on the de- velopment of new processes. This is equally im- portant if your team is new to laser processing or if you are switching from one laser supplier or system model to another . Each system will have different operating characteristics and capabili - ties that impact the process, as well as different software functionality for process development. There will always be certain guidelines that can be followed for flex laser processing, some of which will be discussed in more detail in the next installment of this series. A typical applica- tions training outline might include the follow- ing concepts: Tool overview: How does the laser energy get from the laser output to the work piece? How is power con- trolled? How is the material kept in flat and in place during processing? How does the debris removal mechanism work, how is it used, and what is its importance in consistent processes and optics lifetime? Creating a laser drill file from a CAD file: How does one define alignment points, off- set, rotation, and scaling methods? How does one set laser focus? How are process param- eters and tooling motions (e.g., circles, spirals, punches, routs) added and modified? Developing processes for blind and through vias, routing, and/or patterning: What are the available knobs to affect the process, such as tooling motions, laser power, laser repetition rate, process velocity, and laser focus? How does one best combine various tool- ing motions for any given process? How do blind and through processes differ and what are the as- sociated tradeoffs between throughput and qual- ity/yield? What is fluence and how does it affect material removal? How does one ensure a high yield process with a robust process window? For both operator and process engineer train- ing, there are many important details to cover. Make sure that the personnel to be trained can fully focus on the training. At a minimum, they should be relieved of other engineering or pro - duction responsibilities during the training times and, ideally, distractions such as the use of mobile phones should not be allowed the training room. Initial Operation With operators and process engineers fully trained, your team is now equipped to start de- veloping and running production processes. However, it is common for questions to arise as you start operating the tool. Don't hesitate to stay in touch with your supplier. Especially for those new to laser processing, questions are normal! PCB Mike Jennings is director of product marketing with ESI's Industrial Products Division. Patrick Riechel is product manager for ESI's flexible circuit micromachin- ing tools. To read past columns or to contact them, click here. STEPPING UP TO LASER PROCESSING FOR FLEX, PART 4: INSTALLATION, TRAINING AND INITIAL OPERATION Figure 4: Example of an LED light tower with operation status (red, yellow, green) and interlock defeat status (white) LEDs.