Benchmade Kulgera 930 with S30V steel - having a hard time putting a good edge on it

[Folderguy]

My Benchmade Kulgera 930 with S30V steel is a nice enough knife, but I'm having a really hard time putting a good edge on it. I've worked at it quite a bit, reprofiled the edge, used various sharpening instruments, such as diamond steels, carbide cutters, ceramic sharpeners (including to a dealer who wanted to sell me a ceramic sharpener. I told him if he could get my blade razor sharp with it, I'd buy it. He was unable to do so...) including ending with an old school, horn handled 8 1/2 inch sharpening steel. Basically all to no avail.

I have two other knives with S30V steel: a Zero Tolerance 0400St and a Zero Tolerance 0300, and both those knives reached me in a very dull state and in less that a minute for each was able to bring them to shaving sharpness.

So what gives? It's not like I don't know how to put an edge on a blade (been doing that for over 35 years). Is it possible the heat treatment on the Benchmade is not up to snuff? Oh I can get it to cut, just need to use a coarser grit for a rougher edge, but I like my blades sharp as a razor... easier to snip cigars that way!

Any suggestions as to what I should do to get that Benchmade really sharp will be most appreciated.

Pic below:

Folderguy

 

[Ankerson]

Might want to call Benchmade and send it in..

 

[DallasSTB]

What angle are you trying to achieve? I had to work my 940 and 440 for a fairly long time on my GATCO Pro to get them down to 30º total (like a couple of hours each). Gradually the edge got keener and uniform throughout the length of the blade, until now they are silly sharp. Make sure you spend enough time on the courser stones before moving to the finer ones, keep a consistent angle for a long time, and don't bear down all that hard - let the stones do the work. You should get there.

One thing to note, the 30º angle is more difficult to achieve on the flat-ground 940 and 440 blades due to the additional metal thickness, and this may be the case with your knife as well. I have since gone back to 40º on just about all my EDC knives and it works just fine, and is easier to maintain.

 

[Folderguy]

Might want to call Benchmade and send it in..

As you may have noticed, I've modified the scales. They may not like that if I'm going to send it to them for "repair."

Am I wrong about this?

Thanks for the ideas.

Folderguy

 

[Ankerson]

As you may have noticed, I've modified the scales. They may not like that if I'm going to send it to them for "repair."

Am I wrong about this?

Thanks for the ideas.

Folderguy

I would send it to them anyway since it's the blade you are worried about.

Explain to them the issue and what you have tried etc.

 

[Folderguy]

What angle are you trying to achieve?

Oh, about a 30 would be fine. I've tried all sorts of angles, and have yet to find a way to get it consistently shaving sharp. It will remove a hair or two if I let it dig into my skin, but I'm not really into that.

It is sharp enough to open envelopes and slice paper, but that really doesn't rate too high with me.

Maybe I should just call Benchmade after all, and let them tell me what I'm doing wrong, or maybe they'll just replace the blade, which would be fine. I like the modded scales the way they are.

Thanks.

Folderguy

 

[Folderguy]

I would send it to them anyway since it's the blade you are worried about.

Explain to them the issue and what you have tried etc.

Thanks for the suggestions.

Folderguy

 

[Jason B.]

From what I can see in the pic it looks as though your edge angles are (no offence) sloppy and overly round, I would start with a coarse stone and grind a nice even bevel in it.

 

[KennyB]

Well, I'm not contesting the fact that you know how to sharpen, but exactly what are you doing? I own a 930, and this is what I've done to get mine shaving sharp:

1. Reprofiled on 220 grit to 40 degree inclusive. Raised a burr from choil to tip on both sides.
2. Raised a burr on each side on a 325 grit diamond stone, then on a 750, and then on a 1K water stone
3. Stropped out burr on the 1K water stone
4. Followed up with 50 strops on a home-made strop (scrap leather and a 2x4)

Are you raising a burr on both sides with each abrasive? I've noticed with this knife (not sure if it's because the S30V or what) that it doesn't really like to let one abrasive raise a burr very easily if you haven't already on the last. Even when I get to the 1K, if I don't raise up a burr on both sides, then strop it off, it's not going to come out very sharp.

I would call Benchmade and ask about LifeSharp though. I considered adding some jimping to the back of mine ( on the area above the thumb ramp ) and called them to ask if I could still send it in to LifeSharp. The gal on the phone said that they would just consider it wear and as long as you were just sending it in for Lifesharp and not warranty or repair that they will simply disregard it and sharpen it like usual.

 

[FlaMtnBkr]

Benchmade won't care about the scales. Modifying the scales has nothing to do with the blade which is the issue. I also doubt they will replace the blade because there is a 99.9% chance nothing is wrong with it. They do have a life sharp service though which they will sharpen it up and send it back to you.

S30V can be a pain to get sharp. Todays newer stainless steels aren't like the steels even 15 years ago and require more advanced ways of sharpening. No offense, but if you are using a steel to try and sharpen the knife then it is probably your technique. A steel might make a difference on cheap soft stainless kitchen knives, or even some of the better carbon steels, but it's not going to do much to a high carbide content stainless. Plus a steel is more for aligning the edge than actual sharpening. Oh, and pull through carbide sharpeners are about the worst thing you can use on a nice knife. That is border line abuse as they are terrible.

You need to get a coarse stone and work the bevel until you form a burr or wire edge the entire length of the blade. Then progress to your finer stones like a ceramic to refine the edge and get it really sharp. If all that sounds foreign to you I suggest heading to the maintenance and tinkering forum and reading up some on sharpening technique. Again, no offense meant by all this.

 

[Folderguy]

From what I can see in the pic it looks as though your edge angles are (no offence) sloppy and overly round, I would start with a coarse stone and grind a nice even bevel in it.

Good suggestions.

However, when I'm working a blade over, it shouldn't be that touchy so what you refer to as "sloppy" (no offense taken ) shouldn't be all that critical. By the way, I like my rounded profiles on a blade. Maybe I'm saying something verboten, not my intention, but I like 'em rounded.

The fact is that this knife has given me trouble from the beginning, and it seems to me the steel on this one just plain and simply isn't up to snuff.

It shouldn't be so difficult to get a sharp edge on this blade... Especially considering what I paid for it.

I'm sorry that I forgot to mention that I did raise a burr from both sides and then sharpened it, and steeled it, and so on. I know how to do that. However, that burr looked nice for a bit, then after one or two swipes with the steel and it was alright, and then after just snipping one cigar cap, it felt slightly dull. Perhaps I'm exaggerating a bit, but not by much.

Folderguy

P.S. I combined this answer for two posts, inadvertently. Sorry for the confusion. The other post was made by KennyB.

 

[Folderguy]

Benchmade won't care about the scales. Modifying the scales has nothing to do with the blade which is the issue. I also doubt they will replace the blade because there is a 99.9% chance nothing is wrong with it. They do have a life sharp service though which they will sharpen it up and send it back to you.

S30V can be a pain to get sharp. Todays newer stainless steels aren't like the steels even 15 years ago and require more advanced ways of sharpening. No offense, but if you are using a steel to try and sharpen the knife then it is probably your technique. A steel might make a difference on cheap soft stainless kitchen knives, or even some of the better carbon steels, but it's not going to do much to a high carbide content stainless. Plus a steel is more for aligning the edge than actual sharpening. Oh, and pull through carbide sharpeners are about the worst thing you can use on a nice knife. That is border line abuse as they are terrible.

You need to get a coarse stone and work the bevel until you form a burr or wire edge the entire length of the blade. Then progress to your finer stones like a ceramic to refine the edge and get it really sharp. If all that sounds foreign to you I suggest heading to the maintenance and tinkering forum and reading up some on sharpening technique. Again, no offense meant by all this.

I know that a steel doesn't sharpen, it just aligns the grain on a burr. That's great.

Your suggestions about the coarse and then finer stones and so on to a ceramic are all part of my routine. I suppose I'm not all that prone to get into the nitty gritty of how I sharpen my knives. Suffice it to say that I can put a pretty good edge on any knife... and yes, that will often require coarse stone to reprofile the edge and so on.

I'm not exactly new to all this.

I've bolded up above one of your sentences... and copied it here: S30V can be a pain to get sharp

Maybe that's what I had hoped someone would say. If this supposedly modern stainless is a pain to sharpen, that's not true progress. JMHO

However, my two other knives with S30V sharpen right up, very easily.

They "take" an edge better. The Benchmade 930 with S30V feels almost like it's a bit "slippery" although it's clean, no oil or anything on it. Maybe there are different versions of S30V, or maybe, just maybe, Zero Tolerance's heat treatment is superior to Benchmade's. I have no way to know it one way or the other though.

Folderguy

 

[Jason B.]

Good suggestions.

However, when I'm working a blade over, it shouldn't be that touchy so what you refer to as "sloppy" (no offense taken ) shouldn't be all that critical. By the way, I like my rounded profiles on a blade. Maybe I'm saying something verboten, not my intention, but I like 'em rounded.

The fact is that this knife has given me trouble from the beginning, and it seems to me the steel on this one just plain and simply isn't up to snuff.

It shouldn't be so difficult to get a sharp edge on this blade... Especially considering what I paid for it.

I'm sorry that I forgot to mention that I did raise a burr from both sides and then sharpened it, and steeled it, and so on. I know how to do that. However, that burr looked nice for a bit, then after one or two swipes with the steel and it was alright, and then after just snipping one cigar cap, it felt slightly dull. Perhaps I'm exaggerating a bit, but not by much.

Folderguy

P.S. I combined this answer for two posts, inadvertently. Sorry for the confusion. The other post was made by KennyB.

You can be sloppy to a extent but from what I see its a little over done and is probably your problem. Rounded bevels is what we call convex edge, its a part of hand sharpening that happens but you need to know how far you can go. S30V and other modern steels require you to be more accurate with your formation of the bevel and take double the amount of time needed to sharpen say 440c. Using a carbide scraper or steel is about the worst thing you can do to such a high performance steel, you will never get a properly sharp edge using these methods.

S30V like other CPM steels get unusually sharp at coarse grits, if your grinding with a 320 grit stone your results should be shaving sharp by the time your finished. And like I said, you can be rounded but from what I see your too round.


Take a read through this thread it might help you out a bit. http://www.bladeforums.com/forums/showthread.php?t=732635


P.S. If the steel was bad you would notice a whole lot more wrong with the blade than it not taking a edge. Even a badly HT'ed steel will get razor sharp, in all seriousness you could sharpen aluminum to a shaving edge.

 

[Folderguy]

You can be sloppy to a extent but from what I see its a little over done and is probably your problem. Rounded bevels is what we call convex edge, its a part of hand sharpening that happens but you need to know how far you can go. S30V and other modern steels require you to be more accurate with your formation of the bevel and take double the amount of time needed to sharpen say 440c. Using a carbide scraper or steel is about the worst thing you can do to such a high performance steel, you will never get a properly sharp edge using these methods.

S30V like other CPM steels get unusually sharp at coarse grits, if your grinding with a 320 grit stone your results should be shaving sharp by the time your finished. And like I said, you can be rounded but from what I see your too round.


Take a read through this thread it might help you out a bit. http://www.bladeforums.com/forums/showthread.php?t=732635


P.S. If the steel was bad you would notice a whole lot more wrong with the blade than it not taking a edge. Even a badly HT'ed steel will get razor sharp, in all seriousness you could sharpen aluminum to a shaving edge.

Perhaps it's a little overdone, the sloppiness that is.

That thread you posted is excellent; thank you, very informative.

One thing I'll put in my thinking cap before I buy another knife with S30V is to find out ahead of time if a particular blade takes an edge easily or not.

Thanks again.

Folderguy

 

[Jason B.]

One thing I'll put in my thinking cap before I buy another knife with S30V is to find out ahead of time if a particular blade takes an edge easily or not.

Any steel with high wear resistance will be harder to sharpen, for ease of sharpening you need a lesser steel.

 

[KennyB]

You can be sloppy to a extent but from what I see its a little over done and is probably your problem. Rounded bevels is what we call convex edge, its a part of hand sharpening that happens but you need to know how far you can go. S30V and other modern steels require you to be more accurate with your formation of the bevel and take double the amount of time needed to sharpen say 440c. Using a carbide scraper or steel is about the worst thing you can do to such a high performance steel, you will never get a properly sharp edge using these methods.

S30V like other CPM steels get unusually sharp at coarse grits, if your grinding with a 320 grit stone your results should be shaving sharp by the time your finished. And like I said, you can be rounded but from what I see your too round.


Take a read through this thread it might help you out a bit. http://www.bladeforums.com/forums/showthread.php?t=732635


P.S. If the steel was bad you would notice a whole lot more wrong with the blade than it not taking a edge. Even a badly HT'ed steel will get razor sharp, in all seriousness you could sharpen aluminum to a shaving edge.

I think it's more likely he has a wire edge that's not being removed than the roundness of his bevels. I agree with your points, but owning this exact folder I know this was a problem with me, and I also got it shaving sharp with less-than-perfect bevels.

The thing I noticed with this knife is that burrs are very hard to remove entirely with my usual means. With steels like 440 or AUS8, I could just use a smooth steel to remove the burr, and slice into a piece of wood. With the S30V, this does not do the trick, I have to strop the completed edge on the stone itself to push the burr into a wire's edge, and then strop that wire off.

I'm betting it's a wire not just beacuse I know how difficult it can be to remove them with a steel on this knife, but because you mentioned you thought it was a little duller after cutting a cigar cap. That's a big indicator that you have a wire edge, because they'll quickly dull with use, and while seeming sharp they just won't quite shave.

Since S30V is a harder steel to sharpen, it would make sense it's a harder steel to take care of a burr on as well. That's what I found when I moved on to this steel. Maybe you didn't notice in the Zero Tolerance S30V because it's not quite as hard as Benchmade's?

 

[Jason B.]

I think we need a little understanding of a burr too. You can't remove a burr with a steel and using the wood technique only works on specific types of burrs.

 

[Folderguy]

Any steel with high wear resistance will be harder to sharpen, for ease of sharpening you need a lesser steel.

Lesser in this circumstance can definitely be better, as sharpening a knife while working away from sharpening stones and so on can be easier with a softer steel. In any case, those two Zero Tolerance knives with S30V sharpen very easily.

 

[futz]

My Benchmade Kulgera 930 with S30V steel is a nice enough knife, but I'm having a really hard time putting a good edge on it. I've worked at it quite a bit, reprofiled the edge, used various sharpening instruments, such as diamond steels, carbide cutters, ceramic sharpeners (including to a dealer who wanted to sell me a ceramic sharpener. I told him if he could get my blade razor sharp with it, I'd buy it. He was unable to do so...) including ending with an old school, horn handled 8 1/2 inch sharpening steel. Basically all to no avail.

Mine came from Benchmade pretty dull, with really obtuse and unequal bevels. I reprofiled it with my Gatco diamond hones (freehand) to around 30 degrees and then finished it with the Sharpmaker at 40 degrees. It took some elbow grease for sure - S30V is pretty hard steel - but it's super sharp now. Had no real trouble getting it to take an edge.

If you're not doing already, do the Sharpie trick. Paint the edge black with a Sharpie and then you can see at a glance how you're doing as you remove metal. Do it again for each stage. Wipe the excess off with alcohol or whatever when you're finished.

 

[Folderguy]

Maybe you didn't notice in the Zero Tolerance S30V because it's not quite as hard as Benchmade's?

That's most likely what's happening. The ZTs are probably not hardened as much as the Benchmade. Or maybe they are hardened using a different tempering process.