Spyderco Forums

I am a stainless steel-loving person. I prefer shiny, polished satin finishes on my knives. Some of you like patinas, and I have seen some good patinas. But here is my question: How can someone who does not like rust or patinas like myself enjoy a good steel like CPM Cru Wear or M4, with the assurance that there will be not a single spot of rust on it? And, if it does get rust, what is the easiest way to remove that ugly rust and prevent a patina from starting?

An interesting topic; in my experience (and that is in using very reactive steels in a near-tropical environment) keeping a blade with as you say, "not a single spot of rust" requires measures LIKE the following:

1) no exposure to oxidizing agents such as most plant fluids, sweat, blood, acids, bases etc
2) water wiped off as soon as possible
3) use of a protectant such as Tuff-Glide and I think there are others
4) storage along with a silica gel packet
5) wiping down with an oil like mineral oil or 3-in-1 etc
6) diligent care

I don't mean to suggest that one should go overboard; I mean they are tools and they should be used, not fawned over, but I'm like you in that I appreciate a shiny blade too :) Then again, patinas can be nice, and I have a couple PM2's with natural patinas working!

Calling The Mastiff...

Constant cleaning and oiling.

A patina can be difficult to avoid if you are actually going to use it. Rust is easier to avoid.

Larrin wrote: ↑

Thu Jul 04, 2019 11:55 am

A patina can be difficult to avoid if you are actually going to use it. Rust is easier to avoid.

In a somewhat related question I’ve been meaning to ask you for a while now, chemically/metallurgically speaking, what causes blue-hued patinas? For me, they come about when cutting berries and fatty proteins.

I also found it interesting that, while forcing patinas on Rex 45 and K390 blades using the exact same process at exactly the same time, the Rex 45 took a dramatically bluer hue than did K390. Is it the cobalt content? I also found that K390 was much more susceptible to rust spotting than was Rex 45.

Buy the DLC versions if you can, then you only need to worry about the edge and potentially the pivot area.

I had a Manix 2 in M4 for a good long time- Pocket time and used it exclusively on dry cutting (So no apples or country ham )

I wiped it down with Hoppes #9 every time it went back into the case.....but it still ended up with a mild 'darkening' of the steel around the thumbhole and on the spine jimping....That sounds bad, but I can make a watermelon rust. :D

On the other hand, I have a beater GB1 that I forced a patina with ferric chloride. Never worry about staining that :D

Vivi wrote: ↑

Thu Jul 04, 2019 1:23 pm

Buy the DLC versions if you can, then you only need to worry about the edge and potentially the pivot area.

Came here to say this. My only 52100 and M4 blades are DLC because I didnt like how easily the uncoated versions developed patina and rust/pitting.

Keep it greasy, clean it after every use and grease it up again. Even so, depending on what you cut (food for example) eventually you'll probably need to polish off some amount of patina. This is by no means difficult but it takes more attention than most people are willing to give.

Evil D wrote: ↑

Thu Jul 04, 2019 2:23 pm

Keep it greasy, clean it after every use and grease it up again. Even so, depending on what you cut (food for example) eventually you'll probably need to polish off some amount of patina. This is by no means difficult but it takes more attention than most people are willing to give.

That was another question I had. Would you say most knife users in the world (as opposed to knife enthusiasts) generally prefer stainless steel to carbon steel because, while some claim carbon steel has better cutting power than stainless alloys, stainless is generally easier to maintain from rust/corrosion?

And what that also means (Larrin and other metallurgists, think about this, please!): is that if someone could come up with a way to make a carbon steel stainless, without the need for excess alloying elements like chromium, vanadium, or nickel, they would have a billion dollar idea. Imagine something with the properties of M4, Cru Wear, or 1095, and other tool and carbon steel, but, with the stain proofness of H1 and Lc200N.

basedlarrydavid wrote: ↑

Thu Jul 04, 2019 1:00 pm

Larrin wrote: ↑

Thu Jul 04, 2019 11:55 am

A patina can be difficult to avoid if you are actually going to use it. Rust is easier to avoid.

In a somewhat related question I’ve been meaning to ask you for a while now, chemically/metallurgically speaking, what causes blue-hued patinas? For me, they come about when cutting berries and fatty proteins.

I also found it interesting that, while forcing patinas on Rex 45 and K390 blades using the exact same process at exactly the same time, the Rex 45 took a dramatically bluer hue than did K390. Is it the cobalt content? I also found that K390 was much more susceptible to rust spotting than was Rex 45.

It’s Fe3O4 also called magnetite.

SpyderEdgeForever wrote: ↑

Thu Jul 04, 2019 2:41 pm

Evil D wrote: ↑

Thu Jul 04, 2019 2:23 pm

Keep it greasy, clean it after every use and grease it up again. Even so, depending on what you cut (food for example) eventually you'll probably need to polish off some amount of patina. This is by no means difficult but it takes more attention than most people are willing to give.

That was another question I had. Would you say most knife users in the world (as opposed to knife enthusiasts) generally prefer stainless steel to carbon steel because, while some claim carbon steel has better cutting power than stainless alloys, stainless is generally easier to maintain from rust/corrosion?

And what that also means (Larrin and other metallurgists, think about this, please!): is that if someone could come up with a way to make a carbon steel stainless, without the need for excess alloying elements like chromium, vanadium, or nickel, they would have a billion dollar idea. Imagine something with the properties of M4, Cru Wear, or 1095, and other tool and carbon steel, but, with the stain proofness of H1 and Lc200N.

LC200N is about as "best of both worlds" as I've seen. It has a lot of the same qualities that people love about 1095 but also completely stainless. Otherwise blade coatings are your best bet right now, but you'll still have to deal with edge degradation from oxidation.

Calling The Mastiff...

Sorry, I've been busy staying cool and ducking thunderstorms here.

Anyways, There are no secrets involved. Keep the blade coated to prevent oxidation. If you use it and get salt or corrosive stuff on it just wash it off and reapply the coating.

SEF, with very little time spent you could have researched older threads here and found more than you needed dozens of times over. Do some reading before you ask these things. This place doesn't need anyone driving new posts here. There is lots of traffic here already.

Have a safe and good 4th holiday!

Joe

SpyderEdgeForever wrote: ↑

Thu Jul 04, 2019 10:42 am

I prefer shiny

The Mastiff wrote: ↑

Thu Jul 04, 2019 3:27 pm

Calling The Mastiff...

Sorry, I've been busy staying cool and ducking thunderstorms here.

Anyways, There are no secrets involved. Keep the blade coated to prevent oxidation. If you use it and get salt or corrosive stuff on it just wash it off and reapply the coating.

SEF, with very little time spent you could have researched older threads here and found more than you needed dozens of times over. Do some reading before you ask these things. This place doesn't need anyone driving new posts here. There is lots of traffic here already.

Have a safe and good 4th holiday!

Joe

This is true, though I also wanted to get new knowledge and experience on this from people who may not have read earlier threads on the topic. Thank you and have a great 4th holiday :)

One thing I'll add is I wax my blades with Rennisance wax ( paste wax made for knives, antiques, etc.) now and then. It does the job of oils in sealing oxygen away from the surface and when applying cleans and sort of micro polishes the surface cleaning stuff off I didn't know was there. I especially recommend it for storage purposes. It will even clean off the sort of rust you can pick up from a day in your pockets here in the summer. As long as the steel isn't pitted or gotten deep it does really well. You would want to apply it after you wash the salt off the blade from your sweat and dry it. For me it takes less than 5 minutes to wash, dry then wax the blades. Maybe 10 the first time you do it. The wax also isn't going to trap grit like heavy oils can. I can't stress enough to always use clean rags on blades. Trapped grit scratches blade surfaces and oily stuff interferes with a good wax application and polishing.

Joe

Keep it in the box...

"Victorinox multi tool oil" was the best stuff I ever tried in this regard. It's also food grade. The coating lasts a long time, it's very sticky to the touch so it's very hard to remove completely even if just a thin film is present, as long as the knife is not washed with soap or detergent.

Some people mentioned waxes. I can tell you from experience, they don't fully cover all the pores of the steel and you will get corrosion spots/pitting in certain areas when the environment is particularly corrosive, which would be avoided if using oils in that same situation.

Some people mentioned waxes. I can tell you from experience, they don't fully cover all the pores of the steel and you will get corrosion spots/pitting in certain areas when the environment is particularly corrosive, which would be avoided if using oils in that same situation.

I've heard that before but it isn't my experience. Naturally just like oil it gets rubbed or scraped off when used but other than that it has worked better than oils for me. I have knives that have been stored for 2 or more years ( O1, L6, 1095) that are just like the day they were put up. I don't recommend wax for internal locks and bearings as I find them not as slippery but for corrosion resistance it has been spectacular. I use it on old blued rifles as well as it keeps fingerprints from etching which will happen in less than an hour here in the summer heat and humidity. I also despise oils and sweat combined on my skin from knives or guns and avoid it when I can. It gets pretty bad on the range outside on summer training days here where it's in the high 90's with the dew temp 75 or more. :)

Maybe it's the type of wax you used. Oh yes, I'm not recommending Renn wax for food use but slicing an apple or three has never ruined the taste or been noticeable. I just think there are safer products for food prep knives.

Joe