I am engraving a pipe tomahawk head, it's a casting, and I am just eating up the points on my gravers. Cut a line, off goes the point, need to resharpen. I have about 15 square engravers that I sharpen and keep handy when engraving, when one goes dull, I just pick up another one. This head is harrrrrd, super tough. I'll get moments when the line is cutting really good and all of a sudden it doesn't. The steel composition is a mystery to me. I was hoping that the o1 stuff would hold up better, but I gues not. Oh well, just need to sharpen the bunch again.