I would like to hear your opinion on the relationship between the micro bevel(made by SJ) and edge retention.
Here are three cases.
1. Edge is 17 degrees & No micro bevel.
2. Edge is 15 degrees & micro bevel is 17 degrees.
3. Edge is 13 degrees & micro bevel is 17 degrees.
Assuming normal use (= No abuse), will the edge retention be all the same?
If it is different, how can you sort by the best order of edge retention?
Not an expert, just going off my experience. The first thing that comes to mind with any question on edge retention is what kind of steel. High carbon steels hold an edge longer, as a general rule. Also, im my experience. the thinner (lower angle) does not hold and edge as long as a slightly wider (higher angle). I could be wrong, but in my experience, this tends to be the case.
Quote from: sharpco on November 22, 2017, 11:17:06 AM
I would like to hear your opinion on the relationship between the micro bevel(made by SJ) and edge retention.
Here are three cases.
1. Edge is 17 degrees & No micro bevel.
2. Edge is 15 degrees & micro bevel is 17 degrees.
3. Edge is 13 degrees & micro bevel is 17 degrees.
Assuming normal use (= No abuse), will the edge retention be all the same?
If it is different, how can you sort by the best order of edge retention?
I'm going with... 4. Edge retention will be the same.
A lot of assumptions here though... knives are the same, the steel is decent, etc.
Thinning behind the edge (2 & 3) will primarily affect cutting performance, not edge retention. (Whether the user perceives a difference depends on their skill and how they use it).
Since you're ending at the same angle, then edge retention won't differ... (again with the above assumptions).
I agree. The microbevel only does two things :
1. It makes sharpening at a hit grit level (i.e., on the SJ stone) faster,
2. It makes resharpening faster as there is less metal to grind (again, on the SJ tone)
Good luck,
Rich
Quote from: cbwx34 on November 22, 2017, 03:30:29 PM
Quote from: sharpco on November 22, 2017, 11:17:06 AM
I would like to hear your opinion on the relationship between the micro bevel(made by SJ) and edge retention.
Here are three cases.
1. Edge is 17 degrees & No micro bevel.
2. Edge is 15 degrees & micro bevel is 17 degrees.
3. Edge is 13 degrees & micro bevel is 17 degrees.
Assuming normal use (= No abuse), will the edge retention be all the same?
If it is different, how can you sort by the best order of edge retention?
I'm going with... 4. Edge retention will be the same.
A lot of assumptions here though... knives are the same, the steel is decent, etc.
Thinning behind the edge (2 & 3) will primarily affect cutting performance, not edge retention. (Whether the user perceives a difference depends on their skill and how they use it).
Since you're ending at the same angle, then edge retention won't differ... (again with the above assumptions).
In principle I agree with CB, in my understanding the edge retention will be very similar in all three cases. Nevertheless the best edge retention I expect for 3, than 2 and 1.
My reasoning is following: thinning the blade behind the cutting edge should enable to cut with smaller force/stress, which may result in slightly longer edge retention.
Jan
Quote from: ericclement17 on November 22, 2017, 03:10:57 PM
Not an expert, just going off my experience. The first thing that comes to mind with any question on edge retention is what kind of steel. High carbon steels hold an edge longer, as a general rule. Also, im my experience. the thinner (lower angle) does not hold and edge as long as a slightly wider (higher angle). I could be wrong, but in my experience, this tends to be the case.
I agree... (I'm guessing he's putting the edge on the same type of knife).
Quote from: RichColvin on November 22, 2017, 04:24:35 PM
I agree. The microbevel only does two things :
1. It makes sharpening at a hit grit level (i.e., on the SJ stone) faster,
2. It makes resharpening faster as there is less metal to grind (again, on the SJ tone)
Good luck,
Rich
This is true also.
Quote from: Jan on November 22, 2017, 04:33:14 PM
In principle I agree with CB, in my understanding the edge retention will be very similar in all three cases. Nevertheless the best edge retention I expect for 3, than 2 and 1.
My reasoning is following: thinning the blade behind the cutting edge should enable to cut with smaller force/stress, which may result in slightly longer edge retention.
Jan
Good point, and totally agree. (I put what you say under "cutting performance"... but for most users, it translates to "cuts better longer", which is similar to edge retention).
Quote from: Jan on November 22, 2017, 04:33:14 PM
Quote from: cbwx34 on November 22, 2017, 03:30:29 PM
Quote from: sharpco on November 22, 2017, 11:17:06 AM
I would like to hear your opinion on the relationship between the micro bevel(made by SJ) and edge retention.
Here are three cases.
1. Edge is 17 degrees & No micro bevel.
2. Edge is 15 degrees & micro bevel is 17 degrees.
3. Edge is 13 degrees & micro bevel is 17 degrees.
Assuming normal use (= No abuse), will the edge retention be all the same?
If it is different, how can you sort by the best order of edge retention?
I'm going with... 4. Edge retention will be the same.
A lot of assumptions here though... knives are the same, the steel is decent, etc.
Thinning behind the edge (2 & 3) will primarily affect cutting performance, not edge retention. (Whether the user perceives a difference depends on their skill and how they use it).
Since you're ending at the same angle, then edge retention won't differ... (again with the above assumptions).
In principle I agree with CB, in my understanding the edge retention will be very similar in all three cases. Nevertheless the best edge retention I expect for 3, than 2 and 1.
My reasoning is following: thinning the blade behind the cutting edge should enable to cut with smaller force/stress, which may result in slightly longer edge retention.
Jan
Good point. Jan. ;)
I agree with all of the above. I would add that one way to insure that your customers' knives stay sharper longer is to vette them carefully, and accept only those who have excellent technique as paying customers. You may end up bankrupt, however, the edges will stay sharp longer.
On a serious note, I do believe in the value of offering your customers, especially return customers, bits of good advice on keeping their knives in better condition. Maxtheknife, one of our new members who is a veteran sharpener in Virginia Beach, has done a number of youtubes. One shows quite clearly how a dishwasher can damage a knife. Hopefully Max will post a link to it. Once you see it, you will never subject a knife to a dishwasher!
There is much to learn. Let's keep learning.
Ken
Many people think that 15 degrees edge is the best.
If the edge retention is determined by the micro edge, is it better to set the edge angle to extremely low (eg, 10~12 degrees) and then set the micro edge to 15 degrees rather than just sharpening it to 15 degrees? Because it can cut more easily with the same edge retention. (In the case of kitchen knives that are not used harshly)
I would believe most customers' statements about careful use of their knives as much as I would believe their declared weight on their drivers' licenses. That's an unfair generalization, but how many of us will lower our knife preservation standards to get the job done.
I think a straight fifteen degree setting gets the job done for the majority of customers. Even if not always ideal, it would not be considered sloppy work. I would save more heroic procedures for the few very sophisticated customers.
Ken