CPM 3V edge retention not what I expected.

Joe Duder

Joe Duder

Joined
Jan 22, 2013
Messages
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Just purchased a BRKT Aurora in CPM 3V. It was fairly sharp when I received it from the previous owner. I cut up 1/2 of a tri tip roast and cut the tops off of two pumpkins and it was half as sharp. It was however very easy to sharpen. It took a very keen sharp edge with about 15 strops on each side with white compound.

I thought the edge would have held up a lot better. I hear, though it lacks in edge retention, it exceeds in toughness.

Is this normal behavior for CPM 3V?


Thanks,
Duder
 
Not really normal. There is a lot to the edge retention equation - proper heat treat being very important. You can have the best steel in the world with a crappy HT and be underwhelmed. Perhaps the edge was burned in the shop?
 
Not for my fherman,that thing never gets dull, well it seems like it. I keep it honed. It can't speak for BRKT 3v.
 
It was probably a wireedge.
Stropping until it's gone is the cure.

A BR 3V edge will last a long time, but at hrc 58, it takes time to get the wire edge off.


Regards
Mikael
 
I've also heard CPM 3V is difficult to sharpen. But, I saw Virtuovice's video on how he touches up his edge with 15 passes on each side of the blade, on a strop containing white compound and it does work. Is this normal?

What is a wireedge?
 
Has it been sharpened before? Most knife manufacturers, BRKT included, use some type of power equipment to do the final sharpening of their knives. Sometimes that can destroy the heat treat right at the edge. If this is the case, the material right at the edge will need to be sharpened away to get at the good stuff.

I was born and raised in California, moved away in '97. I miss me some tri tip.
 
I don't think 3V is difficult to sharpen, but a wire edge takes more time to get rid of, due to the toughness.
A wire edge is a burr on the edge that occurs during sharpening and is normal.
You remove it by stropping with compound on leather.

I think You will get faster results with black or green compound.
White is for polishing an already sharp edge.

Regards
Mikael
 
I moved this to Maintenance, since you probably have a sharpening problem.

First guess, a burr, also known as a wire edge. When a blade is very sharp, the very edge is very thin, and will flop over under any pressure. You have to break off that wire.

Light sharpening with a tone or ceramic rod or strop at a slightly higher angle than you would use to sharpen will remove that thin extension along the apex. This will leave the durable edge.
 
The whole fifteen passes with white compound thing achieved a hair popping edge. It is probably the sharpest edge in the house. So, the wireedge can get this sharp, but will not stay sharp until you strop it out? I guess when it starts holding a better edge for longer, I'll know I succeeded at removing the wire edge? Is there a faster way to determine if it has a wireedge? Is a wireedge similar to feathers, like in meat cutting terms?

A lot of questions, but I'm feeling like this is way more effort than a customer should be putting forth. Perhaps I should stick with $15 Moras that are ready to go, right out of the box.
 
Last edited:
Joe Duder said:
The whole fifteen passes with white compound thing achieved a hair popping edge. It is probably the sharpest edge in the house. So, the wireedge can get this sharp, but will not stay sharp until you strop it out? I guess when it starts holding a better edge for longer, I'll know I succeeded at removing the wire edge? Is there a faster way to determine if it has a wireedge? Is a wireedge similar to a feather edge, like in meat cutting terms?

A lot of questions, but I'm feeling like this is way more effort than a customer should be putting forth. Perhaps I should stick with $15 Moras that are ready to go, right out of the box.
Click to expand...

Even Mora's need sharpening and they don't stay sharp for long when new.

To Your Q's:
#1 Yes, the wireedge will fold over until it's gone.

#2 Also yes to this.

#3 Look at the edge in sunlight, then You can see it with Your eyes.
You can also hear it when You strop and see the pattern it makes in the leather.

#4 I don't know about meatcutting terms, others maybe can answer this.


Regards
Mikael
 
Just looked up wire edge and I don't think a wire edge is what I'm experiencing. A wireedge seems like one could notice it by touch and sight and I can't feel or see one. Unless you heed a microscope to see one, I don't think that's the problem.
 
I wonder if I sent it to BRKT for spa treatment and expressed my concern with the edge retention, would they test it and prove it to be defective or kosher.

Thanks for the insight Mikael.
 
Joe Duder said:
A lot of questions, but I'm feeling like this is way more effort than a customer should be putting forth. Perhaps I should stick with $15 Moras that are ready to go, right out of the box.
Click to expand...

Joe, do you not sharpen your meat cutting knives and machinery? Anything worth having is going to need some attention. Your car needs tuning and oil changes. Not trying to be a smart @$$ but anything that cuts or saws will need sharpening, as will a $15 mora. A wire edge or more commonly called a BURR is needed to reach a true apex on your blade to make it sharp when sharpening. This means that both sides of the grind have met in the center and your knife is sharp. To remove the burr, you need to abrade or grind it away without creating another burr. This is often done with a fine ceramic stone, or a strop coated with an abrasive compound to abrade or polish the burr away leaving a very sharp knife blade. It is a little more involved than this, but this is what you need to do to get your knife sharp again as it was when you bought it. It has nothing to do with the quality or lack thereof of the knife in question. Hope this helps you understand.

Blessings,

Omar
 
Joe Duder said:
Just looked up wire edge and I don't think a wire edge is what I'm experiencing. A wireedge seems like one could notice it by touch and sight and I can't feel or see one. Unless you heed a microscope to see one, I don't think that's the problem.
Click to expand...

When the wireedge is carefully stropped, You don't see it until it folds over again.
 
Joe Duder said:
I wonder if I sent it to BRKT for spa treatment and expressed my concern with the edge retention, would they test it and prove it to be defective or kosher.

Thanks for the insight Mikael.
Click to expand...

BR will remove the burr, but honestly this is something You need to do for Yourself after any sharpening of the knife.
It's a part of using fine cutlery!

IMO there's no point in getting fine powdersteel cutlery, without taking a deep breath and learn the basics of sharpening.


Regards
Mikael
 
OHALLUM said:
Joe, do you not sharpen your meat cutting knives and machinery? Anything worth having is going to need some attention. Your car needs tuning and oil changes. Not trying to be a smart @$$ but anything that cuts or saws will need sharpening, as will a $15 mora. A wire edge or more commonly called a BURR is needed to reach a true apex on your blade to make it sharp when sharpening. This means that both sides of the grind have met in the center and your knife is sharp. To remove the burr, you need to abrade or grind it away without creating another burr. This is often done with a fine ceramic stone, or a strop coated with an abrasive compound to abrade or polish the burr away leaving a very sharp knife blade. It is a little more involved than this, but this is what you need to do to get your knife sharp again as it was when you bought it. It has nothing to do with the quality or lack thereof of the knife in question. Hope this helps you understand.

Blessings,

Omar
Click to expand...

When you purchase a knife for $200 you don't mind having to sharpen the burr off before you can fully use it? For my money that thing better be ready to go right out of the box. I understand it will need to be sharpened. I don't mind sharpening my knives, I love sharpening them. In fact, it relaxes me.

I did post the Mora comment before I understood what a Burr was. Understanding it better, a burr edge was not what I was experiencing.

Thanks for trying to "help me understand".
 
Joe Duder said:
When you purchase a knife for $200 you don't mind having to sharpen the burr off before you can fully use it? For my money that thing better be ready to go right out of the box. I understand it will need to be sharpened. I don't mind sharpening my knives, I love sharpening them. In fact, it relaxes me.

I did post the Mora comment before I understood what a Burr was. Understanding it better, a burr edge was not what I was experiencing.

Thanks for trying to "help me understand".
Click to expand...


I have received $600 knives that did not have great edges.

A burr or wire edge normally excites me. I have a strop, and after a minute or two a wire edge will come of, leaving a fierce edge. When I sharpen my own knives, I intentionally raise a burr before moving to the strop.
 
"IMO there's no point in getting fine powdersteel cutlery, without taking a deep breath and learn the basics of sharpening."

Maybe your right. I didn't do a whole lot of in depth research on CPM3v and sharpening it. I more or less watched a couple videos and read some threads. I am pretty good at sharpening any of the 10's, 01, S30v, 154Cm. But this is the first 3v knife I've owned. Maybe the Duder needs do some more research.

Oh ya, deep breath.
 
It took a bit before I warmed up to 3V steel.
I just had to change my sharpening habits a little like not letting the edge get too far gone before touching up and realizing how far I need to go with the diamond stones before transitioning to others.

It is nice to try out new steels but I would never abandon old carbon steel or cheapie stainless like AUS8.
 
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