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THE BEGINNER’S GUIDE TO FLAT TABLE CNC MACHINES What to Expect When You’re Expecting a New CNC
By Christine Bergeron, Technical Consultant, Planit Canada Christopher Manclière, Senior Software Specialist, Planit Canada
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ongratulations on your new CNC! Much like the arrival of a new baby, the delivery of your first Flat Table CNC means you have to become an expert at a whole lot of things very quickly. You may find yourself awake in the middle of the night, frantically Googling “what is a controller?”, “vacuum optimization,” or “what does a CNC operator do?”
The first step in knowing how you’re going to operate your new baby is to understand how to communicate with it. Rather than adorable baby-talk, your control software will be in charge of reading pre-programmed commands that tell your machine how to execute actions to make a part. G-Code is a common CNC language, which looks just like a text file that the machine can read and then execute. (Awww! So cute!) Some machines will use proprietary language. The device will only accept the format defined by its controller, and if it doesn’t understand a command, it will stop the 30 WOOD INDUSTRY SUMMER 2021
program’s execution and spit up an error message. Less cute. Creating programs for your CNC, or CNC programming, is done using one of three methods: with a code editor, with CAM software, or with a CAD/CAM software. The code editor is probably the most tedious way to create a CNC program. It requires you to write the G-code from scratch. While it could be a decent solution for making parts with simple operations, it would involve writing thousands of lines of code to execute complex functions. To speed things up, you can use CAM software. This method allows you
to import or draw a CAD file, and the software will automatically generate the CNC program for you. You’ll have a graphic interface allowing you to see your part and verify the machining is correct. Your CNC programmer may need to manually modify operations for each piece before generating the files for the machine. The third option is the CAD/ CAM software which is a fully integrated solution. The same software you use to create your drawing will also generate your CNC program. It will take you from design to manufacturing without requiring the use of 2 or 3 other solutions to create a program for your CNC. Your workflow is simplified, and you won’t need complex programming skills. Now that you can talk to your baby, you’ll need to set up your spoilboard. You want to be thinking about maximizing the vacuum on your CNC to hold parts and make sure they don’t move. Before mounting the LDF or MDF board onto your CNC’s permanent table, you’ll want to ensure you’ve got flat, even surfaces with four sealed edges. We recommend using two coats of paint to seal the edges and prevent bleeding airflow or losing vacuum at the top of the board. Your CNC machine will have a surfacing program for flattening the spoilboard, and every member of your team must be familiar with how to use it. You’ll need to have the right tool - a spoilboard surfacing cutter with a wide diameter. Remember to enter the new board thickness into the controller after running the program. Once in a while,
