PDA

View Full Version : Determining hardness on older knives



gic
07-13-2013, 05:56 PM
This is being probably overly curious but is there a non destructive method one can use at home to determine (roughly) the HRC of an antique knife?

sachem allison
07-13-2013, 07:37 PM
Ray rogers has some schematics on his site so, that you can make your own hardness tester, for cheap. sometimes I see them on the bay used for a couple hundred bucks.

sachem allison
07-13-2013, 07:38 PM
They do make special files but, they are expensive also http://www.amazon.com/industrial-scientific/dp/B001CTI7TE

Benuser
07-13-2013, 08:03 PM
If you know what kind of edge is taken, what is the grain size, and what edge is hold, you have an idea. Should work for old carbons.

gic
07-13-2013, 08:11 PM
Yep it is some old carbon. I'm ust curious because they seem harder than the wusthof and henkels knives I started with (which are 54 or so). They seem almost as hard as some of my softer j-knives 58-59. Is this possible???

franzb69
07-13-2013, 11:47 PM
They seem almost as hard as some of my softer j-knives 58-59. Is this possible???

yup. i've heard of older carbons to be about that hardness. =D

sachem allison
07-14-2013, 12:05 AM
alot of that old carbon can have pretty good harness. Those guys new what they were doing and that virgin carbon steel was amazing stuff. too think all of it was eyeballed back in the day, no pyrometers and heat treat ovens. just experience.

franzb69
07-14-2013, 01:41 AM
Those guys new what they were doing and that virgin carbon steel was amazing stuff. too think all of it was eyeballed back in the day, no pyrometers and heat treat ovens. just experience.

industrial revolution, the dumbing down of skilled workers.

=(

Dan P.
07-17-2013, 09:37 AM
alot of that old carbon can have pretty good harness. Those guys new what they were doing and that virgin carbon steel was amazing stuff. too think all of it was eyeballed back in the day, no pyrometers and heat treat ovens. just experience.


The problem with production knives is probably that the heat treatment computer will be set to the steel manufacturer's (or whoever's) "optimum" temperatures, which means optimum rate of non-breakage, not optimum hardness.