I've found the Fiskars won't split (with one whack) most of what I cut. Seriously, it won't split anything a single bit ax won't, although it does it with a bit more authority. I had high expectations also; reading what the "fans" post you get the idea it the next best thing to a Star Wars Light Saber. But the "reality" is, like any other tool, it has its purpose and use... no more than that. I actually believe it would be a better tool with a good hickory handle on it; but then they couldn't use the "lifetime" sales gimmick... and, of course, the head would need redesign. The cost of the thing (not that it's that much) must be mostly the handle anyway, 'cause the steel ain't all that great... too hard/brittle for a striking/cutting tool.
I use the "one-whack" theory when splittin' wood with ax or maul... if one won't do the job, I'm using the wrong tool (an occasional two whacks if the second is just to break the last few fibers or strings). The Fiskars is not effective on Burr Oak, Ash, Black Cheery, Hackberry, Hard Maple, and (straight) Red Elm... but the maul is. The Fiskars is effective on Silver Maple, White Cedar, Black Walnut (most of it), and standing-dead Pine... it does OK on a few of the others I mentioned after they've been halved or quartered by the maul.
Nothing but hydraulics is effective on American Elm... or, at least, I ain't found anything else. Heck, wedge 'n' sledge ain't even effective.
Some stuff just ain't worth tryin' to split with shoulder power.
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