Is CPM 3V a tough steel to sharpen?

Terry M.

Terry M.

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I just got a knife in this steel and it was fairly dull in my opinion so I put it on my Wicked Edge and followed my ”normal” sharpening routine to 17dps and it’s just not getting sharp as I like. I will say the blade is a thick one and probably will never be an excellent slicer. Maybe I just answered my own question with that last statement. Your thoughts?
 
I just had this experience on my guided sharpener, with a different steel. Turned out I was not quite at the apex. I decided to take it out of the clamps and it turned out it was very easy to fix on the stones, because I was really really close. I could have just dropped down in grit.

I do think that's the most likely cause. Steels much, much worse than 3v can get really sharp. They just can't hold it.

I'd advise you to do what I should have done: make sure the edge cleanly cuts paper before moving to a higher grit. If you are new to the steel, one way it may surprise you is by resisting the sharpening process more than you are used to.
 
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What helps me, and lots others is covering the edge with a black sharpie marker.

I'm in the process of putting the initial edge on a 3V knife now......

Yes, it's Work!

* But once you get it, it's a Beautiful edge, and not bad to maintain
 
If you're using diamonds you shouldn't have any problems. 3V will take a nice edge. As long as it's not a bad heat treat, just keep working with it and you should get a good result.
 
I did use the black sharpie and it appeared I was removing it all but I’m going to try again here in a little bit. Thanks for the advice
 
Terry M. said:
I just got a knife in this steel and it was fairly dull in my opinion so I put it on my Wicked Edge and followed my ”normal” sharpening routine to 17dps and it’s just not getting sharp as I like. I will say the blade is a thick one and probably will never be an excellent slicer. Maybe I just answered my own question with that last statement. Your thoughts?
Click to expand...

A friend had sent me a knife in 3V which I tried to touch up and found to be unresponsive compared to other 3V knives I've owned. Sent it back to him and he found the same. I think the heat treat may have been messed up when it was modified from the original profile. (I won't name the maker so as not to create any controversy.)

So, "maybe" there was an issue with the heat treat...especially if there had been any modifications to the blade following its original build. Just a guess.

Otherwise, 3V shouldn't be a chore to sharpen, especially with diamond or the other quality hones available to you.
 
I’d hate to say it was the heat treat but I’m wondering. I just got done spending 45 mins at a 15dps from 400 grit down to leather strop and it’s still not much better. Definitely getting the marker off the apex. I‘m stumped.
 
Terry M. said:
I’d hate to say it was the heat treat but I’m wondering. I just got done spending 45 mins at a 15dps from 400 grit down to leather strop and it’s still not much better. Definitely getting the marker off the apex. I‘m stumped.
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I don't know what to say other than what I posted above...but is the knife as new? In other words, in the condition it left the maker or manufacturer's facility? (Prior to your sharpening, I mean.) Or was it pre-owned or worked on by anyone else?
 
Terry M. said:
I’d hate to say it was the heat treat but I’m wondering. I just got done spending 45 mins at a 15dps from 400 grit down to leather strop and it’s still not much better. Definitely getting the marker off the apex. I‘m stumped.
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At 15 dps it should feel very sharp even if it is thick stock. And a strop should have cleaned up any burr left on the edge. Will cut hair, phone book paper? How not sharp are we talking?
 
It won’t shave hair or cut phone book paper. That’s what I don’t get. Never had this issue before with a knife
 
Do you have a loupe or some king of magnification to view the apex up close? It's extremely valuable to see what is really going on at the apex. I've sharpened knives that "removed" the sharpie to the naked eye, but inspection under the pocket microscope reveled I was just shy of reaching the apex. I feel they are a must have for sharpening, especially considering how inexpensive budget ones are. My 60-120x pocket microscope was around $12 and it works great for the intended task.
 
Did you kill the edge before you sharpened it? My suspicion in a case like this is that the factory burned the edge when they sharpened it.
 
Strauss95 said:
Do you have a loupe or some king of magnification to view the apex up close? It's extremely valuable to see what is really going on at the apex. I've sharpened knives that "removed" the sharpie to the naked eye, but inspection under the pocket microscope reveled I was just shy of reaching the apex. I feel they are a must have for sharpening, especially considering how inexpensive budget ones are. My 60-120x pocket microscope was around $12 and it works great for the intended task.
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Agree with the above.

Sharpie ink comes off very easily - it can be easily rubbed off the steel without actually abrading the steel underneath the ink. So just looking for the ink to be removed can be misleading or outright deceptive, if trying to detect if the edge has been apexed or even ground significantly.

Sharpie is really only useful for determining, at the very beginning of your setup, that your held angle is correct. But it's not very helpful for actually seeing where the steel is being taken off, after that. Closer inspection is needed for that - look for alteration of the finish or scratch patterns on the bevels, and obviously look for visible thinning of the steel near the apex. Then watch for the burr. And any cutting tests done after that will definitively tell you if the edge is apexed and burred, and as thin as it can be.

My mantra for sharpening is 'The cutting never lies.' Close inspection under well-lit magnification helps when figuring all this out - but there are still other ways to know for certain that what you're doing is working.
 
update

At the advice of one of our fellow members here I reached out to the maker of my knife. I was disappointed that only his marketing manager replied back. I did get some useful info though. He sharpens his knives at a 22-25dps. If I would like to send my knife in he would sharpen it back up for me. :confused:
I’m a little disappointed in the response as I asked some detailed questions but ah well I guess. Before sending it off I’m going to try the loupe you all suggested and see if that helps. Thanks again.
 
If it was sharpened at 22-25 dps and you’re jumping all the way to 15 you’d better get a chair and some water. You’ll be there a while.

I’d recommend smaller jumps of 2-3 degrees and just use it a while until it’s dull then drop a little more. Say 25 or match the original angle. After it’s dull, resharpen at 22. Next time do 19, and so on until you get where you want.

How wide is the blade? Did you measure the angle or just use the marks on the Wicked Edge? You may be going even lower than you think.
 
Can we see your knife?
22-25?
Ha....... I'll often do less than that Total, not per side.
 
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