A celtic themed coaster I made as a gift this year, inspired by several other coaster designs I found. They are 90mm in diameter and there is a fitting holder included here.

Both are optimized for printing in two colors and with a 0.6mm nozzle, so that wood-filled filaments can be used.

For a nicer look and usability, I attached adhesive felt pads of roughly 1.3mm thickness to the bottom of the coasters, resulting in a total thickness of 4.3mm per piece.

With that, the holder can hold 5 coasters, without felt pads it can hold 8.

I recommend printing the top layer or the complete emblem with as many perimeters as possible. This prevents tiny infill moves, which look/feel rough with most printers (mine included). I've uploaded a screenshot to illustrate this.

If your slicer supports it, It's also a nice feature to use "Hilbert Curve" as the top infill method, because it gives a somewhat natural texture.

If you print them please post a make and tell me in the comments if yours happened to have any problems with hot drinks.

Print Settings

Printer Brand: Prusa

Printer: i3 MK3

Rafts: No

Supports: No

Resolution: 0.2mm

Infill: 100%

Filament: Fillamentum Timberfill light wood tone & cinnamon

Notes:

optimized for 0.6mm nozzle @ 0.66mm line width
printing time for one coaster is ~1h20m

Tested with a freshly brewed cup of tea, didn't show any signs of damage.