That's what doesn't make sense. The Impact Dial doesn't do a little damage; it absorbs impact and sends the same amount of energy out. An impact dial could cause a gust of wind because it's sending the impact directly into air; hence, using the dial on a person's body transfers the energy through the skin into muscles.
That doesn't explain how the Axe Dial works, though. Like the Impact Dial, there's just one orifice, so I can't see how an Axe Dial could "cut" something without having to use it in a sweeping motion. It's going to be powered by the same energy/force as the Impact Dial.
A possibility is that release creates a different distribution, IE, if the Impact Dial releases a ball of energy, the Axe might release energy in the form of a crescent.
EDIT: Ahh, so it's like a bullet versus a kunai?