I remodeled the design by MakeALot to have a high quality STL for my own use.

I use Simplify3D which easily allows me to change print settings throughout the build. This part is split into 2 parts; the base, and the knot. I originally found the model through a Simplify3D tutorial which discuss's this process.

Different Settings for Different Regions of a Model

Base
0.3mm Layer Height
2 Shells
30% Infill

Knot
0.15mm Layer height
2 Shells
0% Infill