Yup. 13 milimeter ≈ 1/2". I had some troubles with the measures so it will be interesting to weigh it. I'd like to see if it's anywhere near 350g (tnx for the info).
Right on! In my experience, the ratio of spike diameter to hole diameter will affect the playability of a toy, as long as you keep that ratio solid you'll end up with a toy that plays well. At a certain point the toy-size to spike-size ratio will become important as well, but it seems like there is more room to play with there. For handturned jumbos I'm fairly sure I use a 9/16" drill bit, but I feel like on the largest ones I've probably used a 5/8" bit as well. Drill bits are like $40 a piece when they're that big!
After I bought my first pill, i was able to get the scramble trick down easily. Couldnt do it with my kendama for some bizarre reason but after i got my hands on my first pill it suddenly just clicked.
I have a blue pill and a red jumbo pill and both are so fun. Someone said it above, but I always let people try the pill when I have it on me because I find they sometimes have more success with it than with a Kendama at first. In the future I want to pick up a hardwood pill. Hats off to Terra