When I was buying a board a while back I looked into hardness and also learned that Janka was testing the side and not the end of the wood, but all over the web they say there is a test for 'end hardness' too, but I could find no charts for end hardness. I did find a site where a bunch of exotic African woods had side versus end hardness comparisons, and the numbers were all over the place. Some end hardness numbers where higher than side hardness and others vice versa. But it was also hard to make heads or tails of the numbers. For example, here is a quote on teak: "The side hardness of teak...is in the range 3730 to 4800 newtons, while the end hardness is in the range 4150 to 4500 newtons." What does that tell me? Not much.
Of course a knife is not a ball bearing, and in the end I just gave up thinking about it and used BoardSmith Dave's FAQs as a reference.
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