03-02-2018, 06:59 PM
(02-15-2018, 10:33 PM)grepper Wrote: I have the feeling that a knife could vary several RHC points over the length of the blade. Is that correct?
it will depend on the hardening process. I heat the entire blade to the same temperature then quench the entire blade. on some blades I tested 10 to 15 different spots and usually had less than 1 point of difference in the readings. example highest of 65, lowest of 64, average of 64.5 with 12 spots tested. a lot of flex is determined by geometry. i make fairly high hardness blades, usually Rc63-65, using low alloy fine grained tool steel (O1 and O7). blades for the kitchen. if dropped on concrete, the tip would probably break off. very small edge angle, usually less than 15 degrees total, with a 10 degree per side microbevel. they can slice boneless protein and 'soft'(nothing harder than a potato) fruits and veg see thru thin. they will go 6 to 8 months between touch-ups on a diamond hone.
the big issue is that there is currently no test anyone can do to show performance. a BESS score is just a measure of sharpness, i don't know how that correlates to slicing ability.