bigger one
thingiverse
A personalized adaptation of http://www.thingiverse.com/thing:44815 was created using the Customizer! Access it at http://www.thingiverse.com/apps/customizer/run?thing_id=44815. For printing, set cursor at 100, edges to 1, include a groove with value of 1, specify diameter as 15, maintain margin at 0.1, choose type 1, and set weight as 11. Also, ensure $fn is set to 50 for optimal results.
Download Model from thingiverse
With this file you will be able to print bigger one with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on bigger one.