I find that old vehicle springs make a great straight razor. The springs that I have used in the past are on the "lower carbon" side of "high carbon" steels. Don't get me wrong, they are very hardenable but probably less than .70% carbon. These make excellent razors in my opinion. They are easy to hone and stay sharp for a long time when maintained properly with a strop. I find them to be a joy to use and think that it is ironic that "junk steel" can make such a fine instrument. Just curious if anyone else had noticed the same thing?