Ken Onion knife sharpener

gunslinger387

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I only have two CPK’s, a Behemoth Chopper and HDFK. These knives are wicked sharp! I want to keep them that way and not change a thing. Can anyone tell me what angle they are sharpened too?

Thanks,

Kevin
 
I only have two CPK’s, a Behemoth Chopper and HDFK. These knives are wicked sharp! I want to keep them that way and not change a thing. Can anyone tell me what angle they are sharpened too?

Thanks,

Kevin

Welcome to the forum, and congratulations on landing two beautiful blades. I don't know that info off the top of my head but Nathan the Machinist Nathan the Machinist will. There is also an 'ask Nathan a question' thread HERE.

Regards,

David
 
Some more info:

It depends on the knife. The Potato Knife was 15 on one side (zero on the other), some of the A2 Shiv were 23. The Racing Competition Choppers are 15, the EDC are 18, and right now everything else is 20, though the Heavy Chopper may be more than that. There are two versions of Delta 3V, one is on the line between a plate and a lath martensite microstructure, the other is a plate martensite. I use the lath and the 20 edge on choppers and knives that see impact, I use the plate martensite because it supports a thin crisp edge for the small knives at 18 and under. There is no one perfect one-size-fits-all, things are adjusted in places.

So your answer is 20 ;)
 
You might've missed the 'sharpening a CPK' thread, but you might not want to use the Worksharp on a CPK. Distinct possibility of overheating the very edge, potentially messing up the heat treat.
 
Bluemax 1, good looking out. I’ve never had a problem with it causing a blade to heat up. A few smooth easy passes on each side works well and doesn’t even get warm. I think they might be referring to larger commercial grade stuff.
 
Might want to try searching for Nathan's post about using any type of belt sander style sharpener.

He specifically mentions that it's very easy to overheat the extreme edge while sharpening it, because by the very nature of a razor edge, there's very little material there.

The mass of the blade absorbs and dissipates the heat so the blade doesn't seem to 'feel' warm, but it's enough to negatively affect the heat treat at the very edge, that gives D3V the edge retention it's known for.

I happen to have that exact model (got it when there was some ridiculous sale on it), but I've never used it. I'll probably post it up for sale somewhere else.

Here's the thread, referencing another belt type sharpening system, with Nathan's posts.
https://www.bladeforums.com/threads/the-most-incredible-knife-sharpener-i-have-ever-used.1622992/

For reference, that sharpener in the thread, that Nathan says can potentially affect the D3V heat treat, runs at 1000+SFM, IIRC. The Ken Onion Worksharp is variable from 1200 to 2800 SFM
 
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Our powered grinder here that we use for sharpening is also adjustable. We typically adjust between 150 and 300 sfm, and use flood coolant.
 
I have seen many new custom knives with areas on the edge that are blue. That is a good sign that the edge was over heated. I have read complaints about new knives that did not hold an edge until they have been sharpened a few times by hand. Again, that is a good indication that they were sharpened on a belt sander and the edge was overheated.

Just IMHO, of course and we all know what pinions are. ;)
 
Our powered grinder here that we use for sharpening is also adjustable. We typically adjust between 150 and 300 sfm, and use flood coolant.
Interesting, I thought the Ken Onion Work Sharp was actually a lower speed then most belt sharpeners but 1200 sfm minimum is way faster than 150-300 sfm.
 
I have seen many new custom knives with areas on the edge that are blue. That is a good sign that the edge was over heated. I have read complaints about new knives that did not hold an edge until they have been sharpened a few times by hand. Again, that is a good indication that they were sharpened on a belt sander and the edge was overheated.

Just IMHO, of course and we all know what pinions are. ;)

Yes, a small gear or spindle engaging with a larger one.
 
Yes, a small gear or spindle engaging with a larger one.


The Work Sharp is nothing more than a small belt sander, isn't it? Keep in mind that most people who buy things like that have no idea what they are doing and don't really care very much. If they did, they would learn to sharpen by hand. Again, just IMHO.

I have a couple of pull through sharpeners that I have tried over the years. One has diamond plates that don't work very well. The other has small ceramic wheels. That one puts a ragged edge on kitchen knives that cut pretty well, but I don't use either of them. I find that my ceramic "steel" and an occasional touch up on a DMT plate works just fine.

There are also many guided sharpening systems like Edge Pro and Lansky that seem to work OK. (I have never used one.)
 
I use the worksharp from time to time on my knives, mainly Becker and Busse, when they need a serious sharpening and it does fine, otherwise I use strops to maintain them.
Only have had to strop my CPK knives so far, guess I will keep the worksharp away from them and just hand sharpen.
 
Yeah, the reason I never used the KE Work Sharp after getting one a couple of years ago, was the concern about how much metal it might remove quickly, and the potential for affecting the heat treat.

I'm glad I saw Nathan's post in the other thread, as it detailed the specifics in a way I hadn't considered.

The thing is, these types of tools CAN get knives really sharp. The issue is how long it will stay sharp, if you've negatively affected the heat treat of that very fine edge.

Just using it and saying, "Well, it gets my knife razor/shaving sharp", is completely missing what Nate's talking about. The whole point of the D3V protocol, is to produce an optimal blend of toughness and edge retention, which folks who've used these knives hard, for extended periods can attest to.

I have other knives that sharpen easily, and I can get them shaving/hair popping sharp fairly quickly. They don't tend to stay super sharp for very long.

I wouldn't want to chance screwing up whatever it is that Nate's metallurgy testing/magic does, to make CPK's D3V stay sharp the way it does, and his post in the thread I linked to, indicates how easy it might be to affect the heat treat with one of these belt sander type sharpeners.
 
People are going to do what they want to do regardless of informed advice. I have seen nice Randalls and other expensive knives that have been sharpened (?) on bench grinders. Once the knife belongs to you, you can ruin it to your heart's content.

I once complained to customer who wanted us to ship his mint Swedish M38 to a custom gun smith to have it turned into a sporter. He told me that it was his gun and if he wanted to toss it in the street and run over it with his truck, that was his right.
 
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People are going to do what they want to do regardless of informed advice. I have seen nice Randalls and other expensive knives that have been sharpened (?) on bench grinders. Once the knife belongs to you, you can ruin it to your heart's content.

I once complained to customer who wanted us to ship his mint Swedish M38 to a custom gun smith to have it turned into a sporter. He told me that it was his gun and if he wanted to toss it in the street and run over it with his truck, that was his right.
While all of this is absolutely true, the difference is wrt 'informed'.

Oftentimes, folks do, or don't do certain things, simply because they don't know any better.

There's a difference between, "After reading Nathan's post about the mass at the very fine edge, vs mass behind the edge, I now understand how it may be possible to overheat the extreme edge without realizing it"

vs

"I know, and I don't care. The edge retention that CPK is known for, doesn't matter to me. I'll do what I want".
 
While all of this is absolutely true, the difference is wrt 'informed'.

Oftentimes, folks do, or don't do certain things, simply because they don't know any better.

There's a difference between, "After reading Nathan's post about the mass at the very fine edge, vs mass behind the edge, I now understand how it may be possible to overheat the extreme edge without realizing it"

vs

"I know, and I don't care. The edge retention that CPK is known for, doesn't matter to me. I'll do what I want".


That was the point I was trying to make. I was making a general statement, not pointing a finger at anyone.
 
Thanks for the 20/ dps angle info. I've been waiting for Christmas to open the box with the HDFK in it, it's my big present to myself this year. Not that I expect to have to sharpen it for a while but now I know what angle to.
 
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