80mm Spool holder adapter

A spool holder adapter for https://www.thingiverse.com/thing:124649 to hold spool holes larger than 50mm. I design it with FreeCAD and slice it with Cure 15.04, then print it from Octoprint in RepRapPro Mendel Mono with 5mm nozzle, 25% infill, 80mm/s, and no support.