Hardness and RC numbers

[Txcwboy]

I have notice many knifemakers state the RC hardness of their blades on their websites or ads wherever. As a long time collector and budding knifemaker, I couldnt care less if it was Rc 55-57 or 57-59. I guess I dont get it, does it really matter ? If its hardened its hardened right ? or can someone really tell a difference ?

thank you

Dave

[DaveL]

Well, not exactly. Knives are hardened by each maker or heat treater to their desire and the end number, the one you don't care about, is the result. It can vary by heat treat but if one is familiar with the steel, a lot can be judged about the knife by the hardness of the blade. Have you ever seen a Case knife with rockwell hardness? If you are buying a custom knife and found the steel to be sub-standard, the hardness is a factor. The temper is the stage to set the hardness and it varies by that operation. I like to know what I am buying.

[GHEzell]

Originally Posted by Txcwboy

As a long time collector and budding knifemaker, I couldnt care less if it was Rc 55-57 or 57-59.

Dave

You're looking at about a 30% difference in edge holding between 59 and 55 rockwell. It matters quite a bit, and is very noticeable if one actually uses the knife.

[ranger1]

Yes, it does make a differance I personally feel so anyway.On my kitchen knives I use a rc of 55-56 sharpens fast,on my tactical knives I go 58-59 Harder to sharpen great edge holding, Good for opening cans, breaking locks off doors,prying open ammo crates.(so I have been told in feedback from Iraq)I use a 60-61 on skinners,and hunting knives they are a little harder to sharpen hold an edge for a long time.A customer told me he dressed 3 deer,and could still shave with the knife.at this point I feel the blade is great for its intended purpose but may be too brittle for an all around field knife.
The harder the steel the longer it will hold an edge,the longer it will take to sharpen and the easyer it will break.This is strickly from personal experiance.

[Frank Niro]

Ed Caffrey has written a great article on this in these forums. He has a "simple test" that tells whats best also included. Good solid information. Certain hardnesses give best results for certain steels, but Ed's test handles all of those. Frank

[Txcwboy]

OK well I guess I ll pay more attention to this with my new found wisdom Thanks for the enlightenment.

Dave