Remix of Speshulk07's blocks. I wanted them solid for faster printing, and I added labels to the ends so I could tell them apart. I've only used the 12" block, but it has been invaluable.
For paper, I used Dura-Gold - Premium - Longboard Continuous Roll 20 Yards long by 2-3/4" wide PSA Self Adhesive Stickyback Longboard Sandpaper for Automotive and Woodworking from Amazon.
The author remixed this model.