Any problems gluing woods of varying hardness?
I've made a few end grain cutting boards with different types of wood mixed together. One individual thought that over time I might have trouble with the different hardness of the woods I'd glued together. Mostly I used hard maple, hickory and black walnut, but I also included some accents of jatoba and purpleheart. He didn't explain what problems I might experience, and I didn't press him on it.
That was the first I'd heard of potential problems gluing together woods of varying hardness, and I wondered what other wood workers thought of it, and what I should do or avoid doing in the future? I can look at Janka hardness on the wood database--is that what I should be looking at? Is there a maximum difference in hardness I should work within/not go beyond? I see black walnut is Janka hardness of around 1000, but hickory can go as high as 2100. Purpleheart is 2500.