The Axe Has Been Reinvented

“Chopping firewood with traditional axes is often a laborious and even dangerous task. There is always the risk of hitting your own leg with the axe. From this imperfect situation began the pursuit to develop a better axe. It took several years, thinking and testing different exotic methods of chopping wood that were available for purchase at the time, before the idea was born. The traditional axe uses a wedge-shaped head to split the wood, but could this mechanism be improved by using leverage? From this idea the new axe was born, the Leveraxe.

finse hefboombijl

The operational principle of the Leveraxe is totally different from the traditional axe. Upon hitting the top of the log and penetrating it slightly, the leading edge of the axe head begins to slow down. Where the axe blade widens sharply it stops the axe’s penetration. However, the mass of the axe head still has kinetic energy and the off line center of gravity forces it to rotate eccentrically down towards the wood. This rotational movement causes the leading edge, or sharp edge of the blade to turn in a lever action, forcing a split with all the force of the kinetic energy of the axe multiplied by the leverage of the axehead. The widening blade edge also has a benefit in that it helps to prevent the axe from penetrating into the wood and getting stuck there as is often the case with traditional axes.

The 1.9kg axe head has a significant amount of kinetic energy when it begins the rotational movement. While the centre of gravity of the head continues first to the right and then downwards the edge moves in a rotational direction to the left. This movement uses the rotational torque to split a log and push it away from the wood. In total the edge opens the wood by 8 cm. When the axe has rotated sideways it has used most of its energy and ends on top of the log on the in a sideways fashion. This safety feature ensures that the axe does not continue towards your legs and the axe remains totally in control. In addition, the axe holds the log steady on the chopping block ready for the next swing.”

The Finnish Leveraxe. Via Boing Boing and Hackernews. Thanks to Thomas Varney and Brice Waegenire.