This model is a 3D Celtic Knot cube generated using the seed 12. It matches with the 2D version that uses the same seed and can be found here: http://shpws.me/3L1b.
Like the 2D version, the model has four loops and the weave has been set to add a gap between the threads where they cross. In the final print though, many of the threads have fused together at the intersections. Nonetheless I'm really impressed with the results and the print works very well in spite of the really quite thin (0.7mm diameter) threads.
Note that the colour image is purely to illustrate the four different threads. The model doesn't actually contain colour data.