Why do most need reprofile?

[LRR]

It seems I have to re-profile almost every new knife I buy. I use the spyderco sharpmaker and few knives match the angle. It seems most have a much greater angle than the 20 degrees. I can understand that custom knives will be more random, but production knife angles are intentional. This can be a headache on tough blades.

 

[9blades]

For the most part companies sharpen by hand. spyderco, kershaw, and benchmade all do. I've heard around 2 to 3 degrees is an acceptable amount of variation. take this with a grain of salt, I've never actually heard this from someone that works for these companies.

 

[ChapmanPreferred]

Most knife companies create edge geometries that are designed to be more durable and will not cause too many warranty issues for most users (both informed users and un-informed users/abusers). So when informed knife users are ready to sharpen, the angle is larger than would ever be required and the thickness at the edge is too thick for exceptional cutting performance. That means that most knives will require reprofiling to the Sharpmaker angles and may need to be back beveled as well to perform well at general cutting tasks. The payoff for all the hard work is a cutting tool that separates matter very efficiently and is a pleasure to use.

Reprofiled edge = easier maintenance in the future.

 

[LRR]

Thanks for the input. Makes me think twice before buying a new user. I have noticed that spyderco is pretty close (as it should be since they make the sharpening system).

 

[Ben Dover]

Apparently, the companies think you are buying the knife for splitting stove-wood.

I've had "big name" folders as obtuse as 23-25 degrees. One "expensive"' big name blade I bought new was 23 degrees on one side and 25.5 on the other. (Apparently, some of these outfits have never heard of precision CNC machining.):jerkit::jerkit:

Therefore, I just assume, before I buy it that I will have to re-bevel the blade. I like 15 degree bevels on most blades since I use an axe for splitting stove wood.

(An exception was my recently acquired Spyderco Mule Team MT17 of K 390. Both sides were exactly 17.5 degrees, so I went straight to sharpening with no re-beveling.

 

[Nullity]

Apparently, the companies think you are buying the knife for splitting stove-wood.

I've had "big name" folders as obtuse as 23-25 degrees. One "expensive"' big name blade I bought new was 23 degrees on one side and 25.5 on the other. (Apparently, some of these outfits have never heard of precision CNC machining.):jerkit::jerkit:

Therefore, I just assume, before I buy it that I will have to re-bevel the blade. I like 15 degree bevels on most blades since I use an axe for splitting stove wood.

(An exception was my recently acquired Spyderco Mule Team MT17 of K 390. Both sides were exactly 17.5 degrees, so I went straight to sharpening with no re-beveling.

I don't know of any company that does not sharpen by hand.

The only reason I reprofile is to match the bevel angles to my natural freehand angles so when I resharpen the knife I just hold it naturally.
I don't really care about perfectly symmetrical bevels anymore.

To answer the OP, I think that factories err on the side of caution and make the edges tougher to decrease warranty returns.

 

[Jason B.]

Sometimes I think people expect WAY too much from a factory edge. They are only there to make a knife useable and will never be as precise as a hand sharpened edge on stones. I sharpen hundreds of knives weekly and a large number of those are done on a 2x72 grinder, no matter how good I can make it look its never even close to what I can do by hand.

Production knife angles intentional?

That's funny, you do realize the only reason they state any angle at all is so they don't have to keep answering the question "what angle are your knives sharpened at?"

 

[Ben Dover]

I don't know of any company that does not sharpen by hand.


Do you mean they're ALL dinosaurs??

I don't really care about perfectly symmetrical bevels anymore.


But many of us do.

To answer the OP, I think that factories err on the side of caution and make the edges tougher to decrease warranty returns.

I think that is absolutely correct. In our modern age, most fathers no longer teach their offspring the proper use of tools and weapons the way our fathers did!:grumpy::thumbdn:

 

[HwangJino]

I always widen bevel.

factory edges are to protect the average consumer.

 

[Ben Dover]

Many Japanese knife makers intentionally allow the blade to be dull to allow the user to give it the first sharpening.

I think they refer to that first sharpening as "opening the blade."

 

[LRR]

Many Japanese knife makers intentionally allow the blade to be dull to allow the user to give it the first sharpening.

I think they refer to that first sharpening as "opening the blade."

yes but they are cool.......