Summary

A parametric coaster holder. This one is currently setup for 100mm (10 cm of about 4 inch) square coasters with a total depth of 42mm. If you want something else you can change that.

This comes with a FreeCAD file. The FreeCAD file comes with a spreadsheet where you can put in coaster length, width and total depth and the project will change shape. After that select the body or fillet in outline view and export a new STL.