Securing the workpiece
My CNC machines all have tables made of aluminum extrusions, except for one that uses a piece of plate metal. Both would get ruined if I made a mistake and cut through my workpiece and into the table. Eventually the structure would weaken, and I would have to disassemble the entire Y-axis assembly and replace the table – not something I would relish having to do multiple times. Consequently, as has been mentioned before, I like to put a piece of waste board between my workpiece and the table. The waste board is typically made of MDF or plywood and is sacrificial. However, with a thick piece material on top of my table and under the material I am trying to cut or carve, I have to find a way to bolt the material to the waste board and the waste board to the table.
You can purchase waste boards for your 3018 on Amazon or AliExpress easily enough. These often come with countersunk threaded inserts as well, so that you can secure your board to the table...