TL;DR A friend of mine asked me if I could build something useful with my 3D Printer. He wanted to have something to place his new (and expensive) tamper for ground coffee. I always wanted to design and print something useful on my 3D Printer. And I wanted to learn and use OpenSCAD for a long time. Now I had an excellent reason to learn it. Create the Design I had no experience with OpenSCAD at all when I started this little project.