Twirl 3D Effect Lithophane

This is a remix of http://www.thingiverse.com/thing:389075

I made an STL of the twirl picture, you can make it as a lithophane or maybe swap colors while printing (or use dual head). The base is 1 mm so the pattern is above this 1 mm thickness.

---->Edit 2014-11-25: I added new files, the base and relief separated from each other Edit 2016-09-18: I added another file, TwirlReliefOnlyV2.stl - this one has a flat top and bottom in stead of a bumpy surface due to pixels converted to mesh