fix for gravity spool holder base —

Founded fix for gravity spool holder base models & stl files for printing
Spool holder
Thullen
Eagle Spool Holder
Saber_tooth
Spool Holder
Unherolike
Spool holder Ikea Lack
HonzaLipicka
Spool holder adapter
DIY Beyond 3D
low angle spool holder
David Warboss
Spool Holder
G.design