Let's Twirl Again ....

thingiverse

This customizer lets you build a twirl pattern of any size you desire, paired with a backing plate to add contrast to the design. The pre-created STLs are for a 120mm square mat with a depth of 3mm.\nThe customizer allows you to experiment with colors to get a feel for some alternate contrasts. You can create a custom thickness, specify the layer height you plan to print with, and the number of base layers you want. I've printed with three base layers successfully.\n(The customizer isn't cooperating as expected. It might be due to the size of the scad file. You may need OpenSCAD to make adjustments.)\nYou can pause your print and switch filament after the base layers have been completed, or let it all print in one go with dual extruders that are properly calibrated (http://www.thingiverse.com/thing:1480365).