Police 4 K390

[Doeswhateveraspidercan]

I would like to pose some questions to those of you who own and have used the Police 4 in K390 As well as other versions.

#1.How is the corrosion resistance? What would you compare it to for example 52100, M4? or another tool steel.

#2. Is this "The Police" to purchase or are there other versions you would recommend.

#3. What are the thoughts on the police in VG-10 is that steel comparable to LC200N? in terms of blade retention?

#4. Serrated or partly serrated is the spyderedge similar to the fully serrated Paramilitary 2? I know the spyderedge is different in different models in different years I for one like to be able to lock even a piece of paper in a scallop and expect it to slice paper like a razor.

Thank you very much.

[vivi]

1. K390 has been more corrosion resistant than most any carbon steel I've tried, including 1095, A2, S7, and O1. It's still a carbon steel and will show spotting if you don't dry it off all the way, but maintenance has been surprisingly easy for me so far. Then again, it is winter.

2. If you prefer SE, you'll want the original or a Police 3. Same if you value corrosion resistance over edge holding, edge toughness, and the ergonomic changes. I think the P4 is the best version, but I do plan to switch to Pacific Salts as my go to once the weather heats up.

3. I think VG10 holds an edge better than people give it credit for. I carried a VG10 Police 3 for a decade and I was never dissatisfied with any aspects of the blade steel, whether edge retention, corrosion resistance or the ability to hold the very acute angle I gave it. I have not tried LC200N so I cannot make a comparison with it.

4. I have not tried a SE Para of any flavor. Here is a high res image of the SE Police 3:



If you want to know where you can buy one, I know of a store that has one in stock. I thought about buying one, but I'm pretty happy with my SE Pacific Salt.

[Doeswhateveraspidercan]

Sure send me a private message and thank you for such a nice reply.

[Xplorer]

...
#3. What are the thoughts on the police in VG-10 is that steel comparable to LC200N? in terms of blade retention? ...

VG10 is very comparable to LC200N in terms of edge retention. LC200N is so corrosion resistant that for most people it will effectively be completely rust proof. VG10 may not be as corrosion resistant but it's plenty corrosion resistant for most people. LC200N is also remarkably tough and easy to sharpen. VG10 is also easy to sharpen. I like VG10 very much for it's well rounded set of properties.

All that said...K390 is in an entirely different class with regard to edge retention. It's a special steel in that regard and it's also difficult to find. I am a knife maker and I make most of my knives from Vanax, M390, and V4E/CPM4V. I have never been able to find K390 available for purchase with any consistency. I have a piece that a fellow knife maker sent me and knowing how rare it is, I definitely plan to keep the knife I will make from it. The steel is very hard to grind, and pretty hard to sharpen. Once sharp however, it will cut very aggressively and stay sharp for a ridiculously long time.

I wouldn't discourage anyone from buying a knife in VG10 or LC200N..in fact I would encourage it. But, when a knife is available in K390 you have a special opportunity to buy a knife made from a steel that is hard to find and has amazing edge retention. As amazing as K390 is, one important consideration that you should take very seriously is your own sharpening abilities. If you do not have good sharpening equipment and/or you do not enjoy sharpening K390 may not be such a good choice. It will after all, eventually dull and bringing the edge back to it's potential would be difficult without good sharpening stones and a little experience.

Best regards,
Chad

[Xplorer]

oops. double post..

[TomAiello]

I'm carrying mine today.

> #1.How is the corrosion resistance? What would you compare it to for example 52100, M4? or another tool steel.

I have had no issues, but I live in the desert. I'd rate it as better than 52100.


> #2. Is this "The Police" to purchase or are there other versions you would recommend.

For me, yes. The K390 makes the difference.


> #3. What are the thoughts on the police in VG-10 is that steel comparable to LC200N? in terms of blade retention?

I had a VG-10 Police 3 several years ago and sold it. It just wasn't really anything special. I'd say that it's on par with LC200N in terms of edge retention, but I've never had a Police in LC200N, so I'm not sure I can really make any kind of educated comparison.


> #4. Serrated or partly serrated is the spyderedge similar to the fully serrated Paramilitary 2? I know the spyderedge is different in different models in different years I for one like to be able to lock even a piece of paper in a scallop and expect it to slice paper like a razor.

No idea. For me, K390 is a PE steel. I don't think I'd want to have it in SE.

[DBCOOPER]

I have done nothing to my police 4 besides wipe it off with my shirt and keep it clean, I've had no spec of rust, tho I've noticed it holds a finger print more so then any other knife I've used, and I get the feeling if I left a finger print there for an extended period of time it'd rust or "patina"
And yes I'd say the p4 is the version to get if you can handle a non stainless steel, cuz it can rust

[Doeswhateveraspidercan]

Thank you everyone Just pulled the trigger on a Police 4 K390.

[Tucson Tom]

K390 is in an entirely different class with regard to edge retention. It's a special steel in that regard and it's also difficult to find. I am a knife maker and I make most of my knives from Vanax, M390, and V4E/CPM4V. I have never been able to find K390 available for purchase with any consistency. I have a piece that a fellow knife maker sent me and knowing how rare it is, I definitely plan to keep the knife I will make from it. The steel is very hard to grind, and pretty hard to sharpen. Once sharp however, it will cut very aggressively and stay sharp for a ridiculously long time.

I wouldn't discourage anyone from buying a knife in VG10 or LC200N..in fact I would encourage it. But, when a knife is available in K390 you have a special opportunity to buy a knife made from a steel that is hard to find and has amazing edge retention.

Hi Chad,

I appreciate you making these comments. I picked up the Police 4 in large part because of the K390, but have come to really appreciate that knife in an all around way. More than I thought I would. But I like being reminded of just how special that knife is and how fortunate we are to be able to have a knife like that made with that very special steel. We take too many things in life for granted.

[vivi]

It's funny, K390 is the reason I avoided the P4 the first year it was out due to corrosion concerns. Having used it I feel a little silly, because it has some of the best corrosion resistance of any carbon steel I've used. It's a very special steel. Extremely good edge holding, seems pretty tough, good corrosion resistance for what it is, and I feel it sharpens very easy considering how long it holds an edge. Most steels I've used with edge holding close to this level take a lot longer to sharpen.

[Wanimator]

I absolutely love it. It's wear resistance exceeds m4/HAP-40/REX-45 by a long ish shot. I've started to hone it soley with the fine stone want occaisonaly a strop with Flexcut Gold compound and haven't found it to go dull at all. This is definitely the sweet spot for me, it holds better than too coarse or highly polished edge.

[Doeswhateveraspidercan]

Police 4 K390 arrived yesterday and in pocket today.

I am a bit disappointed in the finish of the blade part of it looks like it got more attention from a buffing wheel or something. Do you think I should contact the seller for an exchange? I did put some mineral oil on the blade hpoing it might even things out a bit.

Is this the onset of Patina with K390? Not familiar with this steel any way to correct it? Thanks.

Not Correct.jpg

[Doeswhateveraspidercan]

Here is what a Police4 in K390 blade looks like new out of the box under the microscope.

[Doeswhateveraspidercan]

Another picture of the K390 police4 Interesting to see how the blade is ground and there is a ledge where it meets the flats

S20181219_0003.jpg

[Xplorer]

I should first say, it's very hard to be sure of anything when looking at a photograph. That said, I would say the first picture does look like a patina may have started to form while it was in the box waiting for an owner to care for it. A little cleaning with Fritz or similar metal polish should take care of that fairly quickly and easily.
This blade is carbon steel so humid environments will cause corrosion and acidic foods will put stains on the blade. You can either choose to keep it wiped down and protect it (mineral oil or vaseline) to maintain the shiny silver blade, or you can embrace the patina. A nice even patina will provide somewhat of a protective barrier against more damaging rust. A patina can be forced on the blade as well.
I do both depending on what I want for a particular knife. My Cruwear Manix is always kept shiny and clean while my 52100 Millie has been developing a healthy natural patina for a few years now. My M4 PM2 has a goofy looking forced patina I did just to see what the patina would look like if I put mustard on the blade .



Here'a 1095 bird and trout knife that I have allowed to patina naturally. It's used in the kitchen regularly and has not been protected for the past 2 years. It doesn't quickly form rust spots any more now that the patina is complete.


My best suggestion is this...if you plan to use it as your EDC, let it patina and even help it form a nice even and complete patina. If you plan to use it only occasionally, polish it now and protect it with a lite coating of mineral oil.

As for the pictures of the grind...from what I can actually see on the pictures it looks like a good grind. I'm not sure exactly what you mean about there being a ledge where the bevel meets the flats. Are you able to get a shot looking down the edge that would show that?

Best regards,
Chad

[Doeswhateveraspidercan]

Thank you for the insightful reply. I was thinking Patina but it looks like a buffing wheel mishap like it was kept in the same place too long. I wonder if it is possible to hand buff the sides of a blade to even things out?

So far I really like this blade it is longer than the Millie's I own and thinner blade stock. Love the back lock as well.

I just now took my thumbnail and placed it on the bevel coming up towards the spine I can feel the ledge it is a transition area I am guessing these are ground around 13 degrees per side. I will likely place this on the Ken Onion and widen the bevels and taper them into the flat stock with a Hamguri or Appleseed shape to further reduce drag.

https://www.spyderco.com/edge-u-cation/ ... de-grinds/

[DBCOOPER]

I'd say if you got about 13°dps I'd keep it there unless your going to be doing hard use, as k390 Imo will hold that edge very well, I have mine at 15dps, and I touch up on the 20dps angle on the sharpmaker and it's held up wonderfully, and I often use my knives harder then most, that's why I have the 20dps microbevel,
Also I'd say that may be a spot of patina from first glance, but it's hard to say from a picture

[DBCOOPER]

I should first say, it's very hard to be sure of anything when looking at a photograph. That said, I would say the first picture does look like a patina may have started to form while it was in the box waiting for an owner to care for it. A little cleaning with Fritz or similar metal polish should take care of that fairly quickly and easily.
This blade is carbon steel so humid environments will cause corrosion and acidic foods will put stains on the blade. You can either choose to keep it wiped down and protect it (mineral oil or vaseline) to maintain the shiny silver blade, or you can embrace the patina. A nice even patina will provide somewhat of a protective barrier against more damaging rust. A patina can be forced on the blade as well.
I do both depending on what I want for a particular knife. My Cruwear Manix is always kept shiny and clean while my 52100 Millie has been developing a healthy natural patina for a few years now. My M4 PM2 has a goofy looking forced patina I did just to see what the patina would look like if I put mustard on the blade .



Here'a 1095 bird and trout knife that I have allowed to patina naturally. It's used in the kitchen regularly and has not been protected for the past 2 years. It doesn't quickly form rust spots any more now that the patina is complete.


My best suggestion is this...if you plan to use it as your EDC, let it patina and even help it form a nice even and complete patina. If you plan to use it only occasionally, polish it now and protect it with a lite coating of mineral oil.

As for the pictures of the grind...from what I can actually see on the pictures it looks like a good grind. I'm not sure exactly what you mean about there being a ledge where the bevel meets the flats. Are you able to get a shot looking down the edge that would show that?

Best regards,
Chad

Those are some nice looking knives, btw how did u apply the mustard to the blade to make ure pm2 look like that? I think it looks awesome

[Doeswhateveraspidercan]

Just Flitzed the blade and it looks like my initial fears were correct this blade has suffered a mistake during manufacture some kind of buffer or belt burn on the one side.

I wonder what would happen if I send it in to Spyderco for warranty evaluation?

Hmmmm You know Sal and Eric the Police is a prime Candidate for LC200N treatment with its length I can cut things in the kitchen like Oranges and grapefruit very nicely

[Deadboxhero]

Just Flitzed the blade and it looks like my initial fears were correct this blade has suffered a mistake during manufacture some kind of buffer or belt burn on the one side.

I wonder what would happen if I send it in to Spyderco for warranty evaluation?

Hmmmm You know Sal and Eric the Police is a prime Candidate for LC200N treatment with its length I can cut things in the kitchen like Oranges and grapefruit very nicely

Sounds cosmetic,
I'd just put it back in my pocket and use it, scratch it and let it patina over time.