This is a coaster with the SpaceX design. Very simple, with an ~1mm lip, to keep your cup from sliding off.
I've found that 3D printed coasters have a tendency to slide around a lot, so I put some 3/8" bumpers on the bottom (I use 6 of them for stability) that I got from Amazon. (http://amzn.to/2qy3L5o - I have no affiliation with that company, but those are the ones I use)
These work very well printing at 0.2mm, with a color change if you can do that.
I'd recommend a more striking Blue. The only blue I have on hand is slightly translucent (WhoBlu from MakerGeeks) and it doesn't show up well. Once I get a better blue, I'll probably re-print this.
SpaceX_Coaster.stl | 1.0MB |