opinons on BM DLC coating?

A

a77

Joined
Aug 12, 2009
Messages
71
I'm looking to buy the 943 Osborne, and I like the look of the black blade (I will be getting a PE) but I don't have any experience with dlc black coated blades.

How 'deep' does the coating go? How easy it is to scratch away?

I think I'll be using this knife for light-duty stuff, but I know eventually it will get scuffed up. For that reason I'm considering not getting the black blade.

Any advice/opinions?

Thanks
 
If scratches on a blade bother you then do not get a coated blade. If it's going to be a straight user then the extra corrosion resistance may be worthwhile depending on your uses. I have coated blades from a lot of different companies and they all are scratched up. Benchmade's coating is no better or worse than the others. Personally I like the look of a well worn coated blade..
525sbk_701.jpg
 
Given enough time and use in abbrasive cutting tasks, the coating will wear away.

Shows you actually use the knife.
 
Benchmade doesn't use a DLC coating on their blades. DLC means "diamond like carbon". What we see on knife blades is a tungsten DLC. Benchmade however uses their proprietary BK1 coating.

I've never used a DLC coated blade, but reportedly they're quite resistant to showing wear. BK1 however isn't very wear resistant, especially if you cut cardboard or wood with it. However, unless you're hacking through sandpaper or concrete and you gouge all the way through the coating, the coating does what it's supposed to do, which is prevent corrosion.
 
The coating does not protect the edge from corrosion, so it is purely cosmetic. A patina on the side of the blade is not going to hamper performance, I'd rather have uncoated than have to deal with scratches. Actually my BK1 coating hasn't scratched but it's wearing off.
 
orthogonal1 said:
That is just plain incorrect. Coatings can protect against rust and corrosion in general, much better than patina.
Click to expand...

Well my edge rusted so I'm pretty sure that the BK1 coating doesn't protect the edge. It only protects the sides of the blade.
 
I can't comment on Benchmade's coating, but I have a Pro-Tech with DLC coating and it is fantastic. I have cut through aluminum window screen and thought I damaged the coating, only to find out a few days later that the coating had abraded the aluminum...so I got a layer of aluminum on top of the coating, which I was able to scrub off in the sink with a fine scotchbrite under running water. End result, the coating still looks brand new after 2 years of edc.
 
The DLC coating rockwells somewhere in the 70's, or maybe 80's, at least that is what I remember reading. I just googled DLC coatings and forund that they are between 1,000-3,000 (formulation dependant) on what I guess is the Vickers scale. What happens in real life is that whatever you are cutting has a tendency to rub off on the coating instead of the coating rubbing off onto it. I use windex or acetone to remove the material that has rubbed off. I'm going to try and find some more info.

Btw, I don't know what the coating is, or the hardness, that BM uses, the one they call BK1. Though it appears to be similar to my DLC coated blades from Zero Tolerance. The BK2 coating is very soft in comparision and is a teflon based coating.
 
After a little searching I found that there are several variables to take into account. Just as a starting point, it looks like 1,000 HV (Vickers Hardness) would equate to the high 60RC's, while 2,000 HV would be around 80RC, and 3,000 HV would fall in the mid 80RC's. Anyway you cut it, ha ha cut it;), DLC is HARD!
 
DLC may eventually scuff in use, but not like you think. Diamond Like Coating is a plasma spray process that sputters carbon onto the surface of the substrate. As said, it can achieve extreme hardness.

How good? Engine builders are using it for cam lifters - Nissan and Hyundai for two. NASCAR is also playing with it for non-roller bearing rocker arms - all wear surfaces treated and in direct contact with pushrods and valve heads.

The firearms industry is now using it on AR 15 internals, and the tool fab makers are applying it to extrusion dies, which reputedly improves life at least 500%.

The reason they are exploiting it is clear - all the listed applications on the internet and related forums are raving about the simple fact it's highly wear resistant.

Anyone, including myself, who has sampled and used a TiN treated blade knows that process is amazing at resisting abrasion. DLC takes that several orders of magnitude beyond.

To actually damage a DLC part, you have to gouge the suface and tear the substrate - cut the underlying material and separate it. The molecular bond is that tight.

Sure, it'll wear. But if Nissan is using it on hydraulic lifters with modern low ZDDP oils, I doubt the average knife user will scuff it much with EDC.

Chopping concrete, well, that's different.
 
It will scuff and slwly come ff if you use your knife a lot. I have it on my BM 710. Generally, I hate coatings but I dont find this kind hampers cutting ability etc. Funny enough, they are actually more sheeple friendly in my experience. I think it is when it gets all scuffed up it really looks like a tool while satin looks fresh and shiny ready for the kill lol.

In any case if you like a shiny clan knife, go with satin. If you use your knife a lot and it may get wet etc go for the coating (in your case id ipt for satin as you use your knife lightly)
 
Thalestin said:
If you use your knife a lot and it may get wet etc go for the coating (in your case id ipt for satin as you use your knife lightly)
Click to expand...

The coating does not protect from rust dulling the edge, so what is the point of the coating? I think I'm missing something here when people say the coating protects the blade. From what does it protect? A patina on the side that has nothing to do with actual use?

Benchmade's BK1 coating does wear. Not only that, but it's not even applied correctly, as dipping it in chemicals remove the coating. That's not supposed to happen with properly applied DLC coating.
 
cotdt said:
The coating does not protect from rust dulling the edge, so what is the point of the coating? I think I'm missing something here when people say the coating protects the blade. From what does it protect? A patina on the side that has nothing to do with actual use?
Click to expand...
Do you like rusty knife blades? Would you feel any pride in owning a fine firearm if it was covered in rust? Would you cruise Main Street in a 1960's Lincoln Continental if it looked like this (would you even feel safe)?

Damage done by rust is irreversible.

Benchmade's BK1 coating does wear. Not only that, but it's not even applied correctly, as dipping it in chemicals remove the coating. That's not supposed to happen with properly applied DLC coating.
Click to expand...
What chemicals? Lye? Turpentine? Xenomorph blood? :confused:

BM's BK1 coating protects against corrosion and the Military's specs for salt water resistance. What more do you need? If you're "dipping it in chemicals" that can actually remove the coating, that would definitely fall into the categories of abuse/neglect/wrong tool for the job.
 
Planterz said:
What chemicals? Lye? Turpentine? Xenomorph blood? :confused:

BM's BK1 coating protects against corrosion and the Military's specs for salt water resistance. What more do you need? If you're "dipping it in chemicals" that can actually remove the coating, that would definitely fall into the categories of abuse/neglect/wrong tool for the job.
Click to expand...

I actually like the patina I get from D2 and M2/M4. These steels don't really get pitting rust, but a beautiful brown patina.

Anyway, it's well known that Militec-1 lubricant (to prevent rust) takes the BK1 coating clean off:

dscf0369v.jpg


Not supposed to happen. This means that Benchmade does not know how to properly apply the BK1 coating. However, I do agree that it doesn't scratch as easily as their previous black coatings.
 
Benchmade's BK1 isn't a DLC coating, it doesn't go into the steel. It sits on top of it. It's a fairly thick powder-coat/paint type coating. I think it's the worst type of coating of the kinds I've seen. Kershaw and Spyderco are much better, their coatings are actually bonded to the steel and aren't just painted/coated on.

DSCF1366.jpg

DSCF1367.jpg

DSCF1368.jpg
 
Ok, so a little background info:

I have an older Benchmade 941 red special edition, with the Boron (BC1) coating and it's bombproof. Unfortunately, for some reason, Benchmade stopped making it. Maybe it was radioactive or something. Anyway, I also have a Kershaw with their DLC, Diamond Like Coating, and it is very nearly indestructible. I also have a new Benchmade 943 with a black coated blade. I took it apart to polish up the pivot surfaces and make it open smooth as butter, and I was surprised how easily the black coating came off. I'm probably going to sell the knife because I'm EDCing fixed blades now.

If I were a collector, I wouldn't hesitate to get the BK coating. If I was going to edc the thing and use the hell out of it I would enjoy the BK coating and if it ever got so bad that I just couldn't stand looking at it, I'd just steel wool it off. BTW, Benchmade will replace your blade for a very small fee.
 
Last edited:
You must log in or register to reply here.
Back
Top