BAL­ANC­ING THE ROCK­WELL HARD­NESS SCALE

Knives Illustrated - - URBAN -

If you’re look­ing at knife specs, you’ll of­ten see the term Rock­well hard­ness or the ab­bre­vi­a­tion RC. The Rock­well rat­ing is a scale to mea­sure the hard­ness of a ma­te­rial. In the case of knives, it mea­sures the hard­ness of steel. The steel is tested by us­ing a di­a­mond-tipped in­den­ter on the steel and com­par­ing the pen­e­tra­tion with known vari­ables.

In knife steels, you of­ten see num­bers rang­ing in the high­40s to low-60s. The lower the number, the softer the steel. Softer steel can be stronger and less likely to chip or break, but will not hold a sharp edge long and thus, will need to be re-sharp­ened more of­ten. High hard­ness will of­fer ex­cel­lent edge re­ten­tion, but can be much harder to re-sharpen and can, at times, be brit­tle.

Gen­er­ally, you’ll only see num­bers in the 40s on items like throw­ing knives that don’t need much of an edge but need tough­ness. Typ­i­cal pocket and hunt­ing knives run in the mid-50s, with spe­cialty steels creep­ing up into the high-50s and low- to mid-60s.

If you want a more thor­ough read on Rock­well hard­ness, check out A.G. Rus­sell’s web­site (Agrus­sell.com). He has the best break­down on the topic that I have ever seen.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.