I am trying to hone a razor to shave ready. I've already tried a few times unsuccessfully. It seems to shave decent in the middle, but not at the toe and heel. I noticed on one side of the blade the bevel area is bit thicker at the toe and heal. And on the other side the bevel is thicker in the middle, and much thinner at the toe and heel. Is this normal? Is the blade slightly bowed in the middle?