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SCALPHUNTER
08-24-2010, 12:32 PM
Hey guys, I am needing some advice from those of you out there who are more knowledgeable than I regarding the Rockwell Scale (HRC). I am thinking about purchasing a specific new handmade "Raindrop" Damascus knife, which is hardened to 52-55 HRC. Most of my knives are further up on the "scale," and this is the first knife I've considered buying with this low of a hardness level. Is this good enough to keep and hold a decent edge, or is it too low that it would need resharpening every time it's used. Basically, I wish to know...is it good, or should I pass it up. Thanks.

EdCaffreyMS
08-24-2010, 12:47 PM
IMO, That's going to be a bit on the soft side. It will be "tough" at that hardness, but that's about 4 points softer than I think a damascus blade should be for good edge holding. 4 points doesn't seem like much, but once you use it, it will seem like a lot.

I have to ask, what combination of steels does the Damascus contain? With a Rc hardness of that level, my suspicion is that it contains mild steel? If that is the case, whoever produced it messed up a bit on the ratio of high carbon to mild steel (that's just MY opinion).

SCALPHUNTER
08-24-2010, 01:21 PM
I haven't got a clue which type steels were used, but I kind of figured this was a little on the soft side, as most of my hand forged knives are around 58-59 on the scale. Thanks for the input.

Kevin R. Cashen
08-24-2010, 06:06 PM
You can see why Ed is so well liked and ruffles fewer feathers than I do, he is a gentleman who handled that answer with much kindness and diplomacy. I totally agree with Ed, but this is one of those things I am not as delicate about since steel strengths and performance are physical facts that shouldn't involve people’s hard feelings in facing them. 52 - 55 HRC is not an acceptable hardness for most blades, and even most mass produced knives can at least top that hardness level. People who taut that low level of hardness will often justify it with all kinds of claims about extra toughness for weird abuse which have nothing to do with cutting things, or make a case that it is easier to sharpen. Yes, and copper or lead are easier to sharpen than steel and they are even harder to break, I just don't want a knife made from them.

If one is going to REALLY abuse a knife, 57 HRC is acceptable if the edge is beefed up to compensate for the loss in strength, 58-60 HRC are good for larger knives depending on the alloys used. For a fine cutter like a caper, skinner or small hunter 60-62 HRC is a nice range for real good edge holding and if a person is really going to respect the knife as a fine cutting tool you can even go higher than 62 HRC. All of this, of course, hinges entirely on the proper steel selection and proper heat treatment.

I would also agree with Ed that the steel could have some additions to the mix that is limiting its potential hardness, not that folks can't short change any steel in heat treating, but poor steel combinations are the most common cause for softer damascus.

SCALPHUNTER
08-24-2010, 09:27 PM
Thanks for the info. I thought it was too soft, but since I'm not an authority on the subject, I figured to verify my suspitions before I commited to this knife. Now I know it's not for me.