Update!! M390, CTS-204p Chipping

[Cle808]

UPDATE!! I have changed to 18 DPS and my issues have all but disappeared. I did have one issue cutting frozen pizza at work causing an edge deformation on the domino but that is it. I'm unsure if adding to the overall angle or just grinding away the factory edge helped with the chipping but it seems to be a non issue now. Thanks everyone, if not for you I may have tossed in the towel and given up on these two as I've never had this problem before.



Im a long time follower having some issues so I decided to create an account. Anyhow I recently purchased a smurf blue pm2 in m390 and the smurf domino in cts-204p. Both are having issues with small chips forming. Both are at 30 inclusive and used for mild to medium edc cutting tasks. I know I can go to 40 inclusive and see if this helps but shouldn't these steels be able to hold at 30. I have a techno, salt and another companys m390 blade sharpened the same and have had no issues with edges. Please enlighten me!

[thombrogan]

Welcome to the forum!

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

[kbuzbee]

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

Spot on.

I suppose you can see this with any steel but I've only noticed it on two hard, high carbide steels I've recently acquired - K390 Urban and Maxamet Native. Especially on the Native I just couldn't get it sharp. The diamond stones were creating chips at every grit and the chips were way larger than the current grit. i.e. the chips created by the 400 plates were larger than the 140's grind pattern. Usually you'd go back up to work those out, but that only made it worse!

I wasn't sure what was going on but I initially resolved it by switching to ceramics which aren't as aggressive. But over time both edges "settled down" and are now behaving as expected.

Theories abound as to the cause (for example - did the edge overheat during factory sharpening?) I have no idea, but the resolution seems to be sharpening it a few times to work through the initial edge.

Good luck with yours,

Ken

[JD Spydo]

I've used my M390 Military model almost constantly in the past two years and I've never yet had any chipping problems with it. Just the contrary I've found M390 to be one of the most high performing and dependable blade steels I've ever used. For all intent and purposes it's just about my all time favorite blade steel. I've used that M390 Millie on some pretty tough jobs and haven't had it fail on me yet.

I've not yet had a blade with CTS-204P but the guys I've talked to who do have the Military model with that blade steel have said good things about it. Actually the CTS-204P Military model is high on my "gotta have" list of models I want to get. But please do keep us posted because I am interested to know what is causing this problem :confused:

[AwayFromMySpydieHole]

Welcome to the forum!

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

Honestly, that's a cop out. M390 *should* be able to hold 15dps no matter what. It's a martensitic steel with quite small particle size and very uniform carbide distribution. Exactly why *wouldn't* it support a 15dps edge?

Unless you're saying spyderco somehow burnt the edge and it's the OPs responsibility to grind the damaged steel away....

[gunmike1]

Welcome to the forum!

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

Thom knows what he's talking about, and spot on as always. Many knives I've had required several sharpening sessions before I got to good steel that wouldn't chip out easily. So give it a little more time on the stones and the chips will likely start to disappear.

[Evil D]

Welcome to the forum!

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

Honestly, that's a cop out. M390 *should* be able to hold 15dps no matter what. It's a martensitic steel with quite small particle size and very uniform carbide distribution. Exactly why *wouldn't* it support a 15dps edge?

Unless you're saying spyderco somehow burnt the edge and it's the OPs responsibility to grind the damaged steel away....

So are you saying a high speed belt sander sharpened, burned, and possibly burred edge should not chip?

It's a common issue with any factory ground bevel, and has been talked about here many many times. You just won't see a steel's true colors until you've gotten into the steel a bit and passed the factory ground bevel.

My best example was my 20CP Para 2, fresh out of the box cutting cardboard and it chipped so bad you could see it with your naked eye. I reprofiled it to 20 inclusive with a 30 micro bevel and it has no chipping issues unless I ding the edge on something.

[AwayFromMySpydieHole]

Welcome to the forum!

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

Honestly, that's a cop out. M390 *should* be able to hold 15dps no matter what. It's a martensitic steel with quite small particle size and very uniform carbide distribution. Exactly why *wouldn't* it support a 15dps edge?

Unless you're saying spyderco somehow burnt the edge and it's the OPs responsibility to grind the damaged steel away....

So are you saying a high speed belt sander sharpened, burned, and possibly burred edge should not chip?

It's a common issue with any factory ground bevel, and has been talked about here many many times. You just won't see a steel's true colors until you've gotten into the steel a bit and passed the factory ground bevel.

My best example was my 20CP Para 2, fresh out of the box cutting cardboard and it chipped so bad you could see it with your naked eye. I reprofiled it to 20 inclusive with a 30 micro bevel and it has no chipping issues unless I ding the edge on something.

Someone didn't read the last sentence of my post....

[Evil D]

Welcome to the forum!

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

Honestly, that's a cop out. M390 *should* be able to hold 15dps no matter what. It's a martensitic steel with quite small particle size and very uniform carbide distribution. Exactly why *wouldn't* it support a 15dps edge?

Unless you're saying spyderco somehow burnt the edge and it's the OPs responsibility to grind the damaged steel away....

So are you saying a high speed belt sander sharpened, burned, and possibly burred edge should not chip?

It's a common issue with any factory ground bevel, and has been talked about here many many times. You just won't see a steel's true colors until you've gotten into the steel a bit and passed the factory ground bevel.

My best example was my 20CP Para 2, fresh out of the box cutting cardboard and it chipped so bad you could see it with your naked eye. I reprofiled it to 20 inclusive with a 30 micro bevel and it has no chipping issues unless I ding the edge on something.

Someone didn't read the last sentence of my post....

No I read it just fine. Yes that's exactly what we're saying. Spyderco factory edges are burned. In fact every factory edge I've ever handled from any knife company that belt or grinder sharpens has been burned and every one of them has proven to be both tougher and had better edge retention after reprofiling.

[VashHash]

My M390 mule and military haven't chipped yet. I'd suggest sharpening past the factory edge and seeing if the problem persist. I have a friend with a CTS-204P para and he hasn't complained about it chipping. It's one of his main EDCs. Now I want to carry my M390 millie

[AwayFromMySpydieHole]

Welcome to the forum!

it might take a few resharpenings before your knives with hold a solid 30° without chipping.

Honestly, that's a cop out. M390 *should* be able to hold 15dps no matter what. It's a martensitic steel with quite small particle size and very uniform carbide distribution. Exactly why *wouldn't* it support a 15dps edge?

Unless you're saying spyderco somehow burnt the edge and it's the OPs responsibility to grind the damaged steel away....

So are you saying a high speed belt sander sharpened, burned, and possibly burred edge should not chip?

It's a common issue with any factory ground bevel, and has been talked about here many many times. You just won't see a steel's true colors until you've gotten into the steel a bit and passed the factory ground bevel.

My best example was my 20CP Para 2, fresh out of the box cutting cardboard and it chipped so bad you could see it with your naked eye. I reprofiled it to 20 inclusive with a 30 micro bevel and it has no chipping issues unless I ding the edge on something.

Someone didn't read the last sentence of my post....

No I read it just fine. Yes that's exactly what we're saying. Spyderco factory edges are burned. In fact every factory edge I've ever handled from any knife company that belt or grinder sharpens has been burned and every one of them has proven to be both tougher and had better edge retention after reprofiling.

I'd be shocked if spyderco agreed with you, that they burn almost every edge they put out. Surely they take measures to not get their edges up to 450+F when sharpening..

Also for clarification's sake, when you say "reprofiling" are you telling me that you grind away metal from the apex? Because the term "reprofiling" means that you changed the secondary angle of the blade. That doesn't necessarily mean you did anything to the apex.

To you, it may mean that you grind away an appreciable amount of steel from the very APEX of the edge. I'm asking, because when I reprofile (which I do to any knife I use, usually down to 12dps-ish) I don't usually grind away steel from the apex. In fact, I don't create much of a burr at all.

And as we all know, unless you're forming one **** of a burr, you're not doing very much of anything to the actual apex of the edge. Forming a burr that you need a loupe to see just isn't going to make a difference in the edge holding, given that the edges are burnt as bad as you say they are. Maybe you're forming a large burr at every grit on purpose, who knows? That's why I'm asking.

[kbuzbee]

Also for clarification's sake, when you say "reprofiling" are you telling me that you grind away metal from the apex? Because the term "reprofiling" means that you changed the secondary angle of the blade. That doesn't necessarily mean you did anything to the apex.

Yeah, if you read what David said, it actually does. If you reprofile from 30° to 20° (I'm reading thus as "all the way to the apex") then add a 30° (micro or not) bevel onto that, you are definitely grinding metal from the apex. You have to be. It may not be much depending on just how "micro" but you have to remove some.

Ken

[Cle808]

Just for clarification I want to add a few things that may help. The edges are not chipping during sharpening, they are showing up during use. All Chips are small but visible with the eye. The PM2 has been sharpened once and has developed a chip again. The domino has been sharpened twice as it had developed chips again after the initial re-sharpening. Each time sharpened I have done a full job through all my stones not touch ups. For sharpening I'm using diamond stones initially then moving to chosera pro for the ultra fine grits and then to 1/2 micron loaded strop and finishing with w bare roo strop.

[MacLaren]

Thats strange. I primarily use 204P, in both a Military and Domino. They've yet to chip. I check them with a 14x loupe. Of course, I'm not real hard on them either. Just general knife use, if you will. And, I'm not discounting what your saying either. For me, 204P has been exceptional blade steel.

[MacLaren]

As a matter of fact, I one time accidentally cut thru some wire with my Domino (204p Bento version) and it rolled the edge. I

[Evil D]

I'd be shocked if spyderco agreed with you, that they burn almost every edge they put out. Surely they take measures to not get their edges up to 450+F when sharpening..

Also for clarification's sake, when you say "reprofiling" are you telling me that you grind away metal from the apex? Because the term "reprofiling" means that you changed the secondary angle of the blade. That doesn't necessarily mean you did anything to the apex.

To you, it may mean that you grind away an appreciable amount of steel from the very APEX of the edge. I'm asking, because when I reprofile (which I do to any knife I use, usually down to 12dps-ish) I don't usually grind away steel from the apex. In fact, I don't create much of a burr at all.

And as we all know, unless you're forming one **** of a burr, you're not doing very much of anything to the actual apex of the edge. Forming a burr that you need a loupe to see just isn't going to make a difference in the edge holding, given that the edges are burnt as bad as you say they are. Maybe you're forming a large burr at every grit on purpose, who knows? That's why I'm asking.

"Burned" sounds so harsh. Let's just put it this way...an edge sharpened for production sake gets some amount of over heating, compared to a freehand or other manual/slow method of sharpening. Because of that you will usually see an improvement in toughness and edge retention (due to the factory ground edge being brittle from the heat). For me it has especially been an issue with very high carbide and very hard steels (ZDP).

Yes, when I reprofile, I take it all the way to the apex. I do make an effort to make as little burr as possible but I definitely remove steel from the entire edge and burrs do happen.

I've also had experiences where the first time didn't quite get the job done, as was the case with that 20CP. It wasn't​until a few significant sharpenings that I started to see less chipping. Before that I had sworn off anything similar to S90V/S110V but they have become my most used steels now and the only chipping I see with them is usually user created.

I can't really fault Spyderco for this because like I said I've seen it with other brands too. My ZT0303 was a butter knife until I reprofiled it.

[Cle808]

Thats strange. I primarily use 204P, in both a Military and Domino. They've yet to chip. I check them with a 14x loupe. Of course, I'm not real hard on them either. Just general knife use, if you will. And, I'm not discounting what your saying either. For me, 204P has been exceptional blade steel.

This is why I'm here I can't figure out what is going on. I have another knife in m390 and is has been wonderful. I would understand if I were using them hard. I'm hoping they will settle out eventually. For now I'm going to try to remember to check the edge after every cut and see when they are occurring.

[MacLaren]

Thats strange. I primarily use 204P, in both a Military and Domino. They've yet to chip. I check them with a 14x loupe. Of course, I'm not real hard on them either. Just general knife use, if you will. And, I'm not discounting what your saying either. For me, 204P has been exceptional blade steel.

This is why I'm here I can't figure out what is going on. I have another knife in m390 and is has been wonderful. I would understand if I were using them hard. I'm hoping they will settle out eventually. For now I'm going to try to remember to check the edge after every cut and see when they are occurring.

No doubt man. I totally understand.
Keep us posted please.

[Evil D]

Just for clarification I want to add a few things that may help. The edges are not chipping during sharpening, they are showing up during use. All Chips are small but visible with the eye. The PM2 has been sharpened once and has developed a chip again. The domino has been sharpened twice as it had developed chips again after the initial re-sharpening. Each time sharpened I have done a full job through all my stones not touch ups. For sharpening I'm using diamond stones initially then moving to chosera pro for the ultra fine grits and then to 1/2 micron loaded strop and finishing with w bare roo strop.

God help me, I fear I'm about to open a can of worms here but here goes anyway.

Try your best edge without any stropping and see how it goes, especially if you can't be certain you're removing burrs and or if you're using the strop intentionally to remove burrs. Some people like to believe that strops are a magical burr eraser but all they do is bend the burr straight or break it off. If that's the case in your situation then that burr getting bent straight instead of cut off is where your chips are coming from. I don't know your technique but it's best to do everything possible on the stones to avoid or prevent excessive burrs.

[toxophilus]

It seems like I am the fourth owner of a PM2 with M390 steel; when received, it had 4 areas where the original grind had been rolled/chipped (see below). I re-profiled it to 18 DPS and have not had any issues with chipping while cutting since then; I've been using it for about 2 months. :spyder: