12 inch version of this pad (https://www.thingiverse.com/thing:2030095)(http://www.instructables.com/id/E-drum-With-Small-3D-Printer-and-Thick-Paper/)
I just designed it and have not printed it yet. I will upload pictures as it is completed.
This project is under development. I will release the detailed production process on this blog.
M6-70mm bolt and nut 10
M3-10mm bolt and nut 20
M3-25mm bolt and nut * 5
1mm thick paper
inner diameter : 303.5 mm
outer diameter : 297.5 mm
shell thickness : 3 mm ( 0.5 mm clearance )