Ö As I se it, knife design and edge types and edge angles, have split up to two developing path. The traditional developing path and the city people developing path. I think I wrote about this earlyer.
Traditionalists never use polished edges, they normally stop sharpening in around 25 micron and a few passes on a leather belt. Traditionals use their knifes in fresh wet wood and other soft materials, they skin and butcher - and their edges holds around 20 degrees total. My chopper have 26 degree edge total.
City people (90% of the population) use knifes in different modern materials, plastic, nylon, rubber, card board, dry hard wood and so on - and they need higher edge angles for this type of materials, it is normal with 40 degree edges total. Polished edges have become modern - but in my mind (I am a traditionalist) there are only Suchi chefs Chefs and sergeants that need polished edges...
Burr removal is necesarry for both developing path - but city people use loupe or microskopes to find the burr and use different methods to remove it. Traditionalist bend the burrdorwards and back and remove it with slicing in wet wood or similar, some like to slice a little in their rubber both
Traditionalists dont use loupe or microskopes.
25 micron edges are a little tothy and tothy edges work nice outdoors, are nice to skin with and work good in fresh meat - not so good in wood.
In my life I take care of my knifes and sharpen my edges perfect at home before I went outdoors for 6 month. My knifes have slightly convex edges (2,5-3 degrees convex sphere) and that make them easy ro maintain by freehand during 6 month. I prefer to maintain my edges daily, often with only a strop (my leather belt).
I like tothy edges on working knifes outdoors.
A knife shall only be as sharp it need to be for its purpouse it is why we, for example, have razors to shave with, thin edges that penetrates hair good - and ghe tothy edge get good grip in hair.
Most of you have filéa knifes for fish. Make an experiment. Make the edge very sharp och polish the edge - and then filéa a salomon. You will feel how the edge slice thru the ribs very simple.
Then, make the edge a little duller - and filéa next fish, now the edge slides above the ribs and dont slice thru them - and your filéa will be "bone free".
Sharp polished edges work nice in some materials - and bad in other magerials. Tothy edges works good in some materials - and bad in others...
You choose the type of edge you shall use (flat, convex, hollow) and then you choose how fine your edge needs fo be for the job you shall do 25, 10, 1 micron - or polished.
Of cause, this is what I do for jobs that need precision, for things that shall be conected to eachother and some on, not for every day fast jobs.
I like precision edges in angles and In my mind the angle are more imortant then if the edge is tothy or not. Very few people know what angle there is on their knifes. Most people think sharpening is to get the edge two sides to meet eachother - in what ever angle. When they meet, they start to cut...
I recomend my customers to by two simple Mora knifes. Their edges holds 11 degrees. I recomend them to make one of the knifes in 11 degrees exactly - and the other knife in 12 degrees exactly. Then start to whittle in some birch wood - and learn to know the differance in hiw they work, how much more force the 12 degree edge needs, how they penetrate the wood, and so on. After that test they know the differance between 11 and 12 degree edges. And - they also start to learn deeper knife and edge knowledge, hiw edges in different degrees work - and why.
2010 I show my sharpening tool Chef for the first time. Chef was the first sharpening tool ever with a built in protractor. This becouse Chef was also the first sharpening tool that could be adjusted for different blade width = Chef allways sharpen knifes with a fixed distance if 28 cm between the edge and the pivot point. So, it was very difficult to know what edge angle it was on your edge bexouse it was difficult to meassure the degrees.
The difference in material thicknes on the cutting edge between 10 and 11 degrees are less then 1/1000 part of 1 millimeter per side of the edge (the differance are, 0.055 mm behind the cutting edge 1/1000 part of 1 mm). Lets say that 1 degree add 2/1000 part of 1 mm on the cutting edge - that is not a lot of material - but - the cutting edge holds about 6/1000 part of 1 mm thicknes - and now you add 20% more material to the edge so it grows to 8/1000 part of 1 mm
The only way to go deeper in to knife knowledge is to know what degrees there is on your edge - and then use the knife your self and evaluate the edge. Then change the degrees - and evaluate the edge again.
If you do not know what angle there is on your knife and ghen change the angle - you do not know where you started, you do not know where you landed, you do not know how long Journey your edge have done - and what can you learn from not knowing? Nothing. You allways start from scratch .
If you know what degrees your edge holds - you understand WHY you need to change the angle, you also know how much you need to change the angle - and allready before you start the change of ghe andre you know the result of what you are doing - and from knowing - you can learn. You never start from scratch again.
That is why I create Chef - and later my other tools with built in protractor.
So, the problem to meassure the degrees on the edge also make people say that "degrees are not so important"... The important thing was to make the both side meet eachother - and no burr - and polish the edge so it looks nice...
This is my opinion and experiance of using knifes outdoors during 60 years in Scandinavia. Here we whiitle with our knifes, we never batoon them, bend with them or chop with them. If we need to chop we het an axe or use a chopper. Our edges hold around 20 degrees total edge. My chopper holds 26 degrees, my Forest axe holds around 35 degrees, and my splitting axe holds 40-45 degrees.
Metall cutting edges holds 90 degrees, axes holds 45 degrees, knifes holds 22 degrees and razors holds 11 degrees is a old saying here. The degrees decreese in halv in every step. Hair needs 11 degrees, wood needs 22 degrees, splitting needs 45 degrees - and metal needs 90 degrees to hold.
Thomas
Traditionalists never use polished edges, they normally stop sharpening in around 25 micron and a few passes on a leather belt. Traditionals use their knifes in fresh wet wood and other soft materials, they skin and butcher - and their edges holds around 20 degrees total. My chopper have 26 degree edge total.
City people (90% of the population) use knifes in different modern materials, plastic, nylon, rubber, card board, dry hard wood and so on - and they need higher edge angles for this type of materials, it is normal with 40 degree edges total. Polished edges have become modern - but in my mind (I am a traditionalist) there are only Suchi chefs Chefs and sergeants that need polished edges...
Burr removal is necesarry for both developing path - but city people use loupe or microskopes to find the burr and use different methods to remove it. Traditionalist bend the burrdorwards and back and remove it with slicing in wet wood or similar, some like to slice a little in their rubber both
Traditionalists dont use loupe or microskopes.
25 micron edges are a little tothy and tothy edges work nice outdoors, are nice to skin with and work good in fresh meat - not so good in wood.
In my life I take care of my knifes and sharpen my edges perfect at home before I went outdoors for 6 month. My knifes have slightly convex edges (2,5-3 degrees convex sphere) and that make them easy ro maintain by freehand during 6 month. I prefer to maintain my edges daily, often with only a strop (my leather belt).
I like tothy edges on working knifes outdoors.
A knife shall only be as sharp it need to be for its purpouse
it is why we, for example, have razors to shave with, thin edges that penetrates hair good - and ghe tothy edge get good grip in hair.Most of you have filéa knifes for fish. Make an experiment. Make the edge very sharp och polish the edge - and then filéa a salomon. You will feel how the edge slice thru the ribs very simple.
Then, make the edge a little duller - and filéa next fish, now the edge slides above the ribs and dont slice thru them - and your filéa will be "bone free".
Sharp polished edges work nice in some materials - and bad in other magerials. Tothy edges works good in some materials - and bad in others...
You choose the type of edge you shall use (flat, convex, hollow) and then you choose how fine your edge needs fo be for the job you shall do 25, 10, 1 micron - or polished.
Of cause, this is what I do for jobs that need precision, for things that shall be conected to eachother and some on, not for every day fast jobs
.I like precision edges in angles and In my mind the angle are more imortant then if the edge is tothy or not. Very few people know what angle there is on their knifes. Most people think sharpening is to get the edge two sides to meet eachother - in what ever angle. When they meet, they start to cut...
I recomend my customers to by two simple Mora knifes. Their edges holds 11 degrees. I recomend them to make one of the knifes in 11 degrees exactly - and the other knife in 12 degrees exactly. Then start to whittle in some birch wood - and learn to know the differance in hiw they work, how much more force the 12 degree edge needs, how they penetrate the wood, and so on. After that test they know the differance between 11 and 12 degree edges. And - they also start to learn deeper knife and edge knowledge, hiw edges in different degrees work - and why.
2010 I show my sharpening tool Chef for the first time. Chef was the first sharpening tool ever with a built in protractor. This becouse Chef was also the first sharpening tool that could be adjusted for different blade width = Chef allways sharpen knifes with a fixed distance if 28 cm between the edge and the pivot point. So, it was very difficult to know what edge angle it was on your edge bexouse it was difficult to meassure the degrees.
The difference in material thicknes on the cutting edge between 10 and 11 degrees are less then 1/1000 part of 1 millimeter per side of the edge (the differance are, 0.055 mm behind the cutting edge 1/1000 part of 1 mm). Lets say that 1 degree add 2/1000 part of 1 mm on the cutting edge - that is not a lot of material - but - the cutting edge holds about 6/1000 part of 1 mm thicknes - and now you add 20% more material to the edge so it grows to 8/1000 part of 1 mm
The only way to go deeper in to knife knowledge is to know what degrees there is on your edge - and then use the knife your self and evaluate the edge. Then change the degrees - and evaluate the edge again.
If you do not know what angle there is on your knife and ghen change the angle - you do not know where you started, you do not know where you landed, you do not know how long Journey your edge have done - and what can you learn from not knowing? Nothing. You allways start from scratch .
If you know what degrees your edge holds - you understand WHY you need to change the angle, you also know how much you need to change the angle - and allready before you start the change of ghe andre you know the result of what you are doing - and from knowing - you can learn. You never start from scratch again.
That is why I create Chef - and later my other tools with built in protractor.
So, the problem to meassure the degrees on the edge also make people say that "degrees are not so important"... The important thing was to make the both side meet eachother - and no burr - and polish the edge so it looks nice...
This is my opinion and experiance of using knifes outdoors during 60 years in Scandinavia. Here we whiitle with our knifes, we never batoon them, bend with them or chop with them. If we need to chop we het an axe or use a chopper. Our edges hold around 20 degrees total edge. My chopper holds 26 degrees, my Forest axe holds around 35 degrees, and my splitting axe holds 40-45 degrees.
Metall cutting edges holds 90 degrees, axes holds 45 degrees, knifes holds 22 degrees and razors holds 11 degrees is a old saying here. The degrees decreese in halv in every step. Hair needs 11 degrees, wood needs 22 degrees, splitting needs 45 degrees - and metal needs 90 degrees to hold.
Thomas