I find that when hewing difficult wood like oak and ash, a slight change in technique makes a world of difference.
Conventional wisdom is that when juggling, you just chop at the end of the juggles to split them off, and you notch the wood in such a way as to yield good results from this practice. This, I might point out, requires you to notch at every significant knot you come across.
However, this works really poorly for white oak, which doesn't like to split. It works poorly for ash and hickory as well, which are other two woods I have some experience with. But it works well for things like walnut and softer woods.
On these other woods, I find it is a better practice to instead of splitting from the end, chop down at them and actually cut off the chunks rather than split them off. The best tool here is an axe with a fairly wide bit, but not a great big broad axe. the gransfors 1900 is about the right size, but I prefer a longer handled axe. For this I use my long handled German rough hewing axe, which is essentially a goosewing on a 30" handle, with a narrower bit (about 8 or 9 inches I'd say) You can do it with a regular choping axe just fine, but I find the larger axe to make the whole process a little faster. When working in teams, German carpenters will do this task with their narrow notching axes.
I suppose that some day I will need to make a video to fully show and explain what all I am talking about with this...
I should explain, I do like the American method too. I think it has its own advantages. The chief advantage of it is that it requires only 2 simple tools, whereas the German method requires a few specialized tools. Not everyone has a goosewing, even fewer people have the special notching axes, and I don't know of anyone that has a rough hewing goosewing type axe like I've got (which I had to buy special from an antiques dealer in Austria, or maybe it was Hungary, and then shortly became available for about 10 times what I paid for mine)
Maybe I just need to make up a video or something to demontrate all of this...
