Customized version of http://www.thingiverse.com/thing:56310

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=56310

Using the following options:

ring_thickness = 2.4
ring_width = 10
objectThickness = 4
objectSize = 30
ring_size = 22.2
shape = 0
Custom = [[-10,-10,0],[-10,-9,0],[-10,-8,0],[-10,-7,0],[-10,-6,0],[-10,-5,0],[-10,-4,0],[-10,-3,0],[-10,-2,0],[-10,-1,0],[-10,0,0],[-10,1,0],[-10,2,0],[-10,3,0],[-10,4,0],[-10,5,0],[-10,6,0],[-10,7,0],[-10,8,0],[-10,9,0],[-9,-10,0],[-9,-9,0],[-9,-8,0],[-9,-7,0],[-9,-6,0],[-9,-5,0],[-9,-4,0],[-9,-3,0],[-9,-2,0],[-9,-1,0],[-9,0,0],[-9,1,0],[-9,2,0],[-9,3,0],[-9,4,0],[-9,5,0],[-9,6,0],[-9,7,0],[-9,8,0],[-9,9,0],[-8,-10,0],[-8,-9,0],[-8,-8,0],[-8,-7,0],[-8,-6,0],[-8,-5,0],[-8,-4,0],[-8,-3,0],[-8,-2,0],[-8,-1,0],[-8,0,0],[-8,1,0],[-8,2,0],[-8,3,0],[-8,4,0],[-8,5,0],[-8,6,0],[-8,7,0],[-8,8,0],[-8,9,0],[-7,-6,0],[-7,-5,0],[-7,-4,0],[-7,-3,0],[-7,-2,0],[-7,1,0],[-7,2,0],[-7,3,0],[-7,4,0],[-7,5,0],[-6,-7,0],[-6,-6,0],[-6,-5,0],[-6,-4,0],[-6,-3,0],[-6,2,0],[-6,3,0],[-6,4,0],[-6,5,0],[-6,6,0],[-5,-8,0],[-5,-7,0],[-5,-6,0],[-5,-5,0],[-5,-4,0],[-5,3,0],[-5,4,0],[-5,5,0],[-5,6,0],[-5,7,0],[-4,-9,0],[-4,-8,0],[-4,-7,0],[-4,-6,0],[-4,-5,0],[-4,4,0],[-4,5,0],[-4,6,0],[-4,7,0],[-4,8,0],[-3,-9,0],[-3,-8,0],[-3,-7,0],[-3,-6,0],[-3,5,0],[-3,6,0],[-3,7,0],[-3,8,0],[-2,-10,0],[-2,-9,0],[-2,-8,0],[-2,-7,0],[-2,6,0],[-2,7,0],[-2,8,0],[-2,9,0],[-1,-10,0],[-1,-9,0],[-1,-8,0],[-1,7,0],[-1,8,0],[-1,9,0],[0,-10,0],[0,-9,0],[0,-8,0],[0,7,0],[0,8,0],[0,9,0],[1,-10,0],[1,-9,0],[1,-8,0],[1,-7,0],[1,6,0],[1,7,0],[1,8,0],[1,9,0],[2,-9,0],[2,-8,0],[2,-7,0],[2,-6,0],[2,5,0],[2,6,0],[2,7,0],[2,8,0],[3,-9,0],[3,-8,0],[3,-7,0],[3,-6,0],[3,-5,0],[3,4,0],[3,5,0],[3,6,0],[3,7,0],[3,8,0],[4,-8,0],[4,-7,0],[4,-6,0],[4,-5,0],[4,-4,0],[4,3,0],[4,4,0],[4,5,0],[4,6,0],[4,7,0],[5,-7,0],[5,-6,0],[5,-5,0],[5,-4,0],[5,-3,0],[5,2,0],[5,3,0],[5,4,0],[5,5,0],[5,6,0],[6,-6,0],[6,-5,0],[6,-4,0],[6,-3,0],[6,-2,0],[6,1,0],[6,2,0],[6,3,0],[6,4,0],[6,5,0],[7,-10,0],[7,-9,0],[7,-8,0],[7,-7,0],[7,-6,0],[7,-5,0],[7,-4,0],[7,-3,0],[7,-2,0],[7,-1,0],[7,0,0],[7,1,0],[7,2,0],[7,3,0],[7,4,0],[7,5,0],[7,6,0],[7,7,0],[7,8,0],[7,9,0],[8,-10,0],[8,-9,0],[8,-8,0],[8,-7,0],[8,-6,0],[8,-5,0],[8,-4,0],[8,-3,0],[8,-2,0],[8,-1,0],[8,0,0],[8,1,0],[8,2,0],[8,3,0],[8,4,0],[8,5,0],[8,6,0],[8,7,0],[8,8,0],[8,9,0],[9,-10,0],[9,-9,0],[9,-8,0],[9,-7,0],[9,-6,0],[9,-5,0],[9,-4,0],[9,-3,0],[9,-2,0],[9,-1,0],[9,0,0],[9,1,0],[9,2,0],[9,3,0],[9,4,0],[9,5,0],[9,6,0],[9,7,0],[9,8,0],[9,9,0]];