thickness behind the edge

[rustyrazor]

Ok. so mostly up to this point i have been eyeballing it on my edge thickness... thin for a bird and trout and thick for a combat/utility and the like. Time to get a little more technical on this, so all things being equal how thick do you guys grind your steels behind the edge for lets say a bird and trout, or a "tactical" knife, designed for hard use?

 

[Big Chris]

I grind most everything thin.
I will rarely leave an edge thicker than .012 before sharpening. The few exceptions are knives that I intend to be camp or hard use.
Kitchen knives I will grind to a zero edge and then lightly stone to apply a microbevel. A hunter or B&T will go to .008-.010" before sharpening.
Thin steel, thin geometry, and thin edges with high hardness is what I am really in to.

 

[rustyrazor]

do you grind it that thin before HT? I build everything for hard use basically unless it's for a knife like a bird and trout or fine slicer. Most of mine are (for lack of a better word) tactical or hard use, but i'd love to maximize the cutting ability without sacrificing the ability to take a beating

 

[stezann]

Your kind of question is gonna unleash a less than useful list of thicknesses.
You have been eyeballing, so you have a lot of examples and you should be able to test what is actually working better for your blades and your steel.
Consider that edge thickness without the sharpening angle is an uncomplete equation for the cutting ability of a knife and its abuse standing capacity.
The "meat" behind the edge doesn't prevent it to become dull, the sharpening angle does, more or less.
The meat will impair the cutting ability and protect the blade from impact.
The ability to take a beating is inversely proportional to the cutting ability, but knives are cutting tool, and i won't put the same efforts into building a beating tool, so i made my choice of compromise

Another consideration: have you ever handled a cheap, standard machete? the blade is often thin and almost filmsy, still it does take a whole load of beating. We shouldn't understimate the capability of the steel.

 

[Hesparus]

Here are my general guidelines:

Gyuto: 0.003" - 0.005"
Nakiri/petty: 0.003"- 0.001"
Honesuki: 0.015"
Ryodeba: 0.015" - 0.03"
European chef's knife: 0.008" - 0.01"
Paring: 0.001" - 0.003"
Tactical/camp: 0.015" - 0.02"
Trout and bird/EDC: 0.005" - 0.01"
Hunter: 0.01" - 0.015"

I use 52100 for almost everything.

 

[rustyrazor]

Your kind of question is gonna unleash a less than useful list of thicknesses.
You have been eyeballing, so you have a lot of examples and you should be able to test what is actually working better for your blades and your steel.
Consider that edge thickness without the sharpening angle is an uncomplete equation for the cutting ability of a knife and its abuse standing capacity.
The "meat" behind the edge doesn't prevent it to become dull, the sharpening angle does, more or less.
The meat will impair the cutting ability and protect the blade from impact.
The ability to take a beating is inversely proportional to the cutting ability, but knives are cutting tool, and i won't put the same efforts into building a beating tool, so i made my choice of compromise

Another consideration: have you ever handled a cheap, standard machete? the blade is often thin and almost filmsy, still it does take a whole load of beating. We shouldn't understimate the capability of the steel.

yep.. handled a lot of everything over the years. just wondering what the guys were doing in theres as "hesparus" noted... as an example of what they use for these types. Steel has already been considered to death as well as heat treat. This is the last part of the equation as i want consistency. I have been "overbuilding" my edge thickness for years in my rough use knives and i want to get them thinner without sacrificing edge toughness. the angle will be in the neighbourhood of 20dps for my beaters to withstand chipping/rolling but if i can do this at a given thicnkess of "meat" behind the edge to maximize cutting ability then that's what i'm striving for. the beaters are built with toughness in mind over cutting ability and the bird and trout knives are designed with cutting efficiency in mind over toughness.