Thread: Razors and knives

I was looking at a knife book yesterday. Why do many custom knives have a relatively low HRC: 59 - 60, 61? There are razors with the same hardness, and obviously both harder and softer... But I never knew this level was also found in custom knives.

And WOW on some of the blades I saw!

Cheers
Ivo

RC 59-60 is a good general range for knives, if you don't have a "Use" defined for the knife. Western kitchen knives from the big marketers are RC56-58 and revered around the world. Japanese knives at RC59 are considered SOFT, averaging RC63-64.

Depending on what you want the knife to do will dictate steel type and RC rating. In custom knives the choices are to great to have an easy simple answer to the question.

Details man, give us details

Probably because a lot of utility knives are abused or used for harder jobs than cutting open boxes or for food so you don't want a very brittle knife (or one that is hard to sharpen in some cases.)

For the most part, 59-60 HRC would be considered "hard" in most types of knives. I Like my knives at least 59 HRC and believe it or not, a lot of razors, like the W&B razors tended to be lower hardness from 58-60 hrc. Razors are best at around 61-63, in my opinion.

The reason knives tend to be lower hardness is because of toughness. The harder steel is, the more brittle it is. Razors aren't designed for hacking, chopping, boning, fighting, etc., all of which bring to bear more lateral and unusual stresses than would be encountered when shaving.

To make the "toughness" issue more prominent, these days, there's an overemphasis on it because in order to become Master Bladesmith, one of the tests is to take a perfectly good knife you made and stick it in a vice and bend the crap out of it 90 degrees without it breaking. Then everyone goes "ooohhhh, isn't that cool". But WTF? That's not what a knife is for, so why all the emphasis on being able to bend it? I'll take something that cuts like crazy and keeps on cutting when everything else got butterknife dull from working.