Ive got a bunch of copper brass aluminum and stainless steel blanks to practice on. The stainless blanks came from amazon and dont have the type of steel labeled but they are stamping blanks and all of them on amazon seem to be 304 stainless steel. I cant get anything but a very shallow cut on them with hss or carbide gravers. They are so hard that going back over a cut barely increases the depth if at all. Ive tried different geometry and nothing will cut these things beyond super fine line cuts. Is 304 steel really this difficult to work with?