He noted that he hadn’t printed it out yet, so I thought that I’d have a go this afternoon, see just how well it turned out. I downloaded the piece from Thingiverse, and printed it out.
The printing went quite well:
Trying to take a decent video showing the illusion was by far the hardest part of this mini-project. This was my best attempt, which I think did the trick. Unfortunately, these balls were a bit big for the job.