Unlike knives, an ax edge needs to be sharp but not overly thin – unless you have a Carpenter’s or other specialty ax that is more for crafting than chopping. With most axes, you want it sharp but still thick, so that it can cut into the wood but it’s going to be resistant to chipping. That’s why you only need to sharpen every 3 to 6 months – you don’t need to give an axe a razor edge, it just needs to be able to give the wood a good BITE.