I can’t believe how long it’s been since I last posted. I’ll ensure I contribute more often.
Here are some pictures of the coring of a 20” half-log of red oak I was able to acquire. The end result was 5 rough-turned bowls that are now drying. The largest is 19 1/2” and the smallest is 7 1/2”. It took me one hour to rough-turn the outside of the blank and 1:45 to core the 5 bowls.
-- Ken in Sharbot Lake, Ontario