Welcome, Guest
Username: Password: Remember me

TOPIC: Interesting video... do you destress your edge?

Interesting video... do you destress your edge? 11 months 1 week ago #13449

  • razoredgeknives
  • razoredgeknives's Avatar
  • OFFLINE
  • Platinum Boarder
  • Posts: 697
  • Thank you received: 293
  • Karma: 38


Interesting observation and theory about how the edge can get "burnt" at the factory and have an initial low sharpness/edge holding ability.
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13452

  • Mikedoh
  • Mikedoh's Avatar
  • NOW ONLINE
  • Platinum Boarder
  • Posts: 445
  • Thank you received: 104
  • Karma: 14
If I'm understanding this, the overheating only goes so far? Which makes sense, compared to my former idea that the entire blade was ruined.
Also wondering, if quenching in water to cool blade in s30 is wrong, is there then a proper medium to quench in?
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13453

  • razoredgeknives
  • razoredgeknives's Avatar
  • OFFLINE
  • Platinum Boarder
  • Posts: 697
  • Thank you received: 293
  • Karma: 38
I have heard it explained that if you are grinding a blade on a belt sander, and it gets hot, you need to mist spray it, not actually dunk it in cold water as this can cause "micro-fracturing" of the edge.

This is something that the WEPS really shines at since its not powered...when I remember to, I take my 1k diamond stone and destress the edge before I begin the sharpening process. The diamonds are nice because they don't wear when you do this, unlike water stones (which your blade can actually cut into).

When the knives from from the factory they are sharpened on powered equipment... it is only the edge that can possibly be damaged because that is what is contacting the belt and it is very thin, so it builds up heat quickly.
The administrator has disabled public write access.
The following user(s) said Thank You: Mikedoh

Interesting video... do you destress your edge? 11 months 1 week ago #13454

  • Mikedoh
  • Mikedoh's Avatar
  • NOW ONLINE
  • Platinum Boarder
  • Posts: 445
  • Thank you received: 104
  • Karma: 14
So then de stressing the edge is getting rid of the damaged area by running the stone perpendicular to the knife edge?
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13455

  • razoredgeknives
  • razoredgeknives's Avatar
  • OFFLINE
  • Platinum Boarder
  • Posts: 697
  • Thank you received: 293
  • Karma: 38
exactly! only 1 or 2 passes w/ 1k is enough...
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13456

  • Mikedoh
  • Mikedoh's Avatar
  • NOW ONLINE
  • Platinum Boarder
  • Posts: 445
  • Thank you received: 104
  • Karma: 14
No need for the multi de stress / sharpen as talked about in the video?
If sharpening is involved, just a cursory to 400 or 600 ? Then whittle some wood?
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13463

  • cbwx34
  • cbwx34's Avatar
  • OFFLINE
  • Moderator
  • Posts: 1260
  • Thank you received: 413
  • Karma: 92
I do believe that making a cut into a stone is beneficial on some blades... it provides a nice clean surface to form a new edge. But, I question some of what's in this video...

At 1:08 he shows a new knife. Notice how much metal is now gone from the knife (he also mentions around the 3:10 mark that the sharpening choil is "gone".) I doubt he did that in his 3 destress/sharpening routines. So, why, after all that metal removal, is the edge suddenly better... and that it's now a heat related issue? He could have (probably) cleaned up the edge from the previous use (which from his description was pretty harsh), but I would think that the heat related issues he claims would have been gone long before?

I often find that just sharpening a knife a couple of times will improve sharpness. My guess is that the knife "matches" (can't think of a better word right now) how I sharpened it, so the 2nd, 3rd, etc. time, it will improve. He also did other things to it... thinned the entire blade for example, that would have improved it. Maybe the simpler answer is, after 7 years his sharpening ability improved? :dry: (No idea, just suggesting there's other reasons).

So, yes, IMO, there's some validity to cutting into a stone and providing fresh metal to sharpen will result in a better edge, but not sure I buy the reason in the video.
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13503

  • limpy88
  • limpy88's Avatar
  • OFFLINE
  • Junior Boarder
  • Posts: 28
  • Thank you received: 10
  • Karma: 3
Where is the proof that they dipped the blade in water after grinding. Thats a ridiculous notion. I would imagine that would get one fired at a knife company.

I have heard reports of the s30v chipping. And it is a pain to sharpen both benchmade and ZT. It makes since that the edge could have been overheated when grinding. As it takes me 2-2.5 longer time wise to sharpen s30v compared to 440c.
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13504

  • razoredgeknives
  • razoredgeknives's Avatar
  • OFFLINE
  • Platinum Boarder
  • Posts: 697
  • Thank you received: 293
  • Karma: 38
cbwx34 wrote:
I do believe that making a cut into a stone is beneficial on some blades... it provides a nice clean surface to form a new edge. But, I question some of what's in this video...

At 1:08 he shows a new knife. Notice how much metal is now gone from the knife (he also mentions around the 3:10 mark that the sharpening choil is "gone".) I doubt he did that in his 3 destress/sharpening routines. So, why, after all that metal removal, is the edge suddenly better... and that it's now a heat related issue? He could have (probably) cleaned up the edge from the previous use (which from his description was pretty harsh), but I would think that the heat related issues he claims would have been gone long before?

I often find that just sharpening a knife a couple of times will improve sharpness. My guess is that the knife "matches" (can't think of a better word right now) how I sharpened it, so the 2nd, 3rd, etc. time, it will improve. He also did other things to it... thinned the entire blade for example, that would have improved it. Maybe the simpler answer is, after 7 years his sharpening ability improved? :dry: (No idea, just suggesting there's other reasons).

So, yes, IMO, there's some validity to cutting into a stone and providing fresh metal to sharpen will result in a better edge, but not sure I buy the reason in the video.

Good observations Curtis... My answer to your first question (why is it suddenly better) I would say that it depends upon 1. how damaged the edge was at the factory (in terms of depth from the edge to the spine" and 2. how many times it was sharpened over those 7 years. These are two variables that we don't know... Cliff could have removed a bunch of steel during those sharpenings or not much. Anyway, that is his theory and it makes sense, but I would like to see some metallurgical data that shows heat treated steel can be damaged w/ only heat.

I have heard that it takes not just heat but also TIME to damage temper... don't know how true this is? I will probably be able to speak w/ a metallurgist tomorrow so I will def. ask :side:
The administrator has disabled public write access.

Interesting video... do you destress your edge? 11 months 1 week ago #13506

  • razoredgeknives
  • razoredgeknives's Avatar
  • OFFLINE
  • Platinum Boarder
  • Posts: 697
  • Thank you received: 293
  • Karma: 38
limpy88 wrote:
Where is the proof that they dipped the blade in water after grinding. Thats a ridiculous notion. I would imagine that would get one fired at a knife company.

I have heard reports of the s30v chipping. And it is a pain to sharpen both benchmade and ZT. It makes since that the edge could have been overheated when grinding. As it takes me 2-2.5 longer time wise to sharpen s30v compared to 440c.

While I don't have any proof at this point =) Think about it... dunking your blade in a bucket of water while using it (post heat treat) with a belt sander is a pretty common practice, otherwise you WILL over heat it if you are doing any serious amount of metal removal or reprofiling (which you would be to put the final edge on it post heat treat). It may or may not be the case, but is an interesting theory none the less.
The administrator has disabled public write access.
Time to create page: 0.135 seconds