K390 Patina questions....would your force it in a coastal environment?

[hookahhabib]

So my Mule has made it to Mexico and I'm now thinking about the patina. I live less than half a mile from the beach, and the ocean air is a master of corrosion.

I'm thinking to force a patina as a lot of this knife's work will happen at or very near to the beach.

Being mango season right now, they are all over the place in this town soI know I could very easily apply a mango patina or some sort of mango/pineapple combo, but I'm curious about your suggestions.


What would you do with your k390 mule to address the corrosion issue?

If forcing a patina, what would you use for your own knife?


thanks

 

[RevDevil]

Cold blue it, or soak it in mango juice.

 

[Surfingringo]

Hey rev, I am thinking to get a gayle Bradley and was wondering the same thing as I am beachfront here. This would obviously be an edc/work knife, not a fishing knife. Does forcing a patina increase rust resistance? If so, do you have a reference for a thread or video showing how to properly go about this? I'm not interested in cosmetics, just functionality.

Any advice appreciated,

Lance

 

[bdmicarta]

Does forcing a patina increase rust resistance? If so, do you have a reference for a thread or video showing how to properly go about this? I'm not interested in cosmetics, just functionality.

The guys in the Becker subforum are masters at applying the patina. You can search there. You might also be able to find videos on youtube if you search for something like "knife patina".

 

[HWF]

Lance you have been bitten hard! I love it!

I normally don't 'force' a patina on my knives, but I use them as much as possible every single day especially in the kitchen. This forms a patina very quickly. I prefer shallots and garlic because I eat a ton of them. Cutting fruit, chopping vegis, and using my knife with my fork with every meal has brought much success in my patina efforts.

 

[KNaB]

Hey rev, I am thinking to get a gayle Bradley and was wondering the same thing as I am beachfront here. This would obviously be an edc/work knife, not a fishing knife. Does forcing a patina increase rust resistance? If so, do you have a reference for a thread or video showing how to properly go about this? I'm not interested in cosmetics, just functionality.

Any advice appreciated,

Lance

Apple cider vinegar will give a grey patina. Leave it long enough and you will get a very dark grey with the m4.

 

[RevDevil]

Hey rev, I am thinking to get a gayle Bradley and was wondering the same thing as I am beachfront here. This would obviously be an edc/work knife, not a fishing knife. Does forcing a patina increase rust resistance? If so, do you have a reference for a thread or video showing how to properly go about this? I'm not interested in cosmetics, just functionality.

Any advice appreciated,

Lance

Lance, you can do the same thing on the CPM-M4 and it will keep the steel stabilized to some extend and prevent severe rusting. Yu might some some very light (and I mean light) corrosion, but it can usually be wiped off with a oily rag. The Bradley Folder is awesome, you'll love it.
Try the Cold Blue found in the camping and sporting section of almost any larger store, or you could do a fruit, mustard, vinegar, or other chemical patina. The mango makes the steel look blue as it starts forming, looks cool. Videos are all over YT, but it's not much effort, you can basically stick the entire blade into a mango for example, leave it in for about an hour, check every 30 minutes or so to see if that is the color you want.

 

[Surfingringo]

Lance you have been bitten hard! I love it!

I normally don't 'force' a patina on my knives, but I use them as much as possible every single day especially in the kitchen. This forms a patina very quickly. I prefer shallots and garlic because I eat a ton of them. Cutting fruit, chopping vegis, and using my knife with my fork with every meal has brought much success in my patina efforts.

Sigh, I know, I'm screwed! Hehe. I kind of hate it that I'm lusting after something new because I haven't even really had time to enjoy what I've already got. I think I would like the gayle Bradley, but I won't be doing any buying for awhile. I think I'm going to start dropping some not so subtle Christmas hints around my girl.

 

[Surfingringo]

Lance, you can do the same thing on the CPM-M4 and it will keep the steel stabilized to some extend and prevent severe rusting. Yu might some some very light (and I mean light) corrosion, but it can usually be wiped off with a oily rag. The Bradley Folder is awesome, you'll love it.
Try the Cold Blue found in the camping and sporting section of almost any larger store, or you could do a fruit, mustard, vinegar, or other chemical patina. The mango makes the steel look blue as it starts forming, looks cool. Videos are all over YT, but it's not much effort, you can basically stick the entire blade into a mango for example, leave it in for about an hour, check every 30 minutes or so to see if that is the color you want.

Thanks rev. I take the corrosion thing into account because of where I live, but I know not to get carried away with that either. I hear guys talking about needing a "salt" knife because they live 20 miles from the ocean and kind of roll my eyes. I live right on the ocean and I have some high carbon tools that I've had here for 15 years and guess what? They're doing just fine! Ocean kayak fishing is one thing and i reserve that for my salts, but I had people tell me I shouldn't get a m4 steel knife because I live near the ocean and it might just disintegrate and I was kind of convincing myself that was true. I had to wake up and see that I was getting a bit carried away. A ittle oil once a month and I think m4 will do just fine...And yeah, I will probably force a patina if that will help a bit. Thanks for the help guys, sorry if I hijacked your thread op.

 

[hookahhabib]

... Thanks for the help guys, sorry if I hijacked your thread op.

no worries brother! more information is never a bad thing and sheeit, considering that we both are gringos hanging somewhere along the Mexican coast - my thread is your thread :thumbup:

I had received similar concerns from friends for wanting to bring an M4 piece down to where I am - foolishness I say!


Insane traffic due to local road construction on the only road out of my area ruled out the possibility of a home depot or sporting goods store trip in search of cold blue today, so instead my mule is currently deep inside some juicy mangos that had just fallen down to street level - i decided to ad a couple squeezes of grapefruit juice as well. will post pics soon!

 

[shunsui]

Here's an interesting thread on forcing a patina.

http://www.bladeforums.com/forums/s...A-Deep-Even-Black-Patina-On-1095-Carbon-Steel

 

[JNewell]

From another forum:

There is growing concern about embrittlement in steels due to acid washing. I have personally seen severe degradation where steels such as S30V, Elmax and S125 were so adversely affected the edge would just crumble in very light use (soft woods, cardboard). There is research now in peer reviewed publications on room temperature and similar soaks with milder acids. A number of other people have reported gross failure in blades which have had forced acid washes which were perfectly fine before the wash.

It can be done, it is possible to do without damaging the steel - however it is a harsh corrosive solution being temperature forced to react with the steel which darkens it by consuming the steel and forming a by product. The steels being discussed here are extremely expensive and go through severe processing to produce extremely refined compositions with low impurities and segregations. It might not be the best idea to subject them to random temperature and acid solutions.

As an absolute minimum, you would have to realize all warranty / service would be off liability, and if the blade was sold or traded and anything happened to it - there is a large liability. All of that being said, a lot of people like how it looks, and will force it on steels which a high Cr content which is very difficult to do for the same reason that they don't rust as both are oxidization processes.

If there is demand for coated blades, Spyderco would be the one to do that as they could offer sprint runs with various coatings which can be made of any color, type, finish, especially on steels which have a high heat resistance.

 

[Surfingringo]

Interesting. Maybe the best bet is just buy it, use it, and take care of it.

 

[hookahhabib]

thought provoking stuff from Cliff (as always!) - i imagine he's talking more about hot vinegar patinas (on stailness steels as well since he mentions the high cr content?)

I assume that using fruit and organic matter that a knife will encounter in normal use should not cause a significant amount of damage to the blade (or any damage at all), otherwise wouldn't any kind patina be harmful to steel?


update on my mule: it got a 2 hour mango patina last night and its pretty even with a nice shade of grey, along with the occasional swirls of color when the light is right. Not nearly as dark as I expected it to be based on the only other mango patina I did (that was on an O1 blade) but I like these results more....I'm going to leave the blade patina as is and let the rest of it form through normal use - I already see changes just from the food prep I've done this morning

Since the handle will be wrapped before getting proper scales, I just started another mango patina only for the handle section - depending on how it looks I will then wrap it, or apply plum for a little while and then wrap it...I'm concerned about corrosion due to moisture retention in the handle wrap and think that a couple layers of patina may offer more protection? Does anyone have any experience regarding this theory of mine?

I posted some mediocre pics last night in my other thread about the mule so you can see how the patina was as of last night there....once I'm all done with todays projects I'll update with better quality pics

 

[yoda4561]

Hydrogen embrittlement should fix itself in a matter of hours with the type of soaking you would do for a patina. That's for simple carbon and spring steels though, I'm not sure if it affects stainless alloys the same way.

 

[goodeyesniper]

Thanks rev. I take the corrosion thing into account because of where I live, but I know not to get carried away with that either. I hear guys talking about needing a "salt" knife because they live 20 miles from the ocean and kind of roll my eyes. I live right on the ocean and I have some high carbon tools that I've had here for 15 years and guess what? They're doing just fine! Ocean kayak fishing is one thing and i reserve that for my salts, but I had people tell me I shouldn't get a m4 steel knife because I live near the ocean and it might just disintegrate and I was kind of convincing myself that was true. I had to wake up and see that I was getting a bit carried away. A ittle oil once a month and I think m4 will do just fine...And yeah, I will probably force a patina if that will help a bit. Thanks for the help guys, sorry if I hijacked your thread op.

lol, pretty funny, especially considering how high the rust resistance of m4 actually is. its a really maintenance free steel as long as you are comfortable with some very light discoloration.

as far as forcing a patina, I don't do it. however, when I get a new, non stainless blade I generally do a lot of tasks that will get a patina started. this was easier said than done on m4, thing wouldn't stain for the life of me cutting up fruits and meat as snacks until I realized it would take sitting around much longer than carbon steels with fruit on the blade.

I doubt patina really offers much protection. I think the main thing is it makes it harder to see new staining. if it comes to red rust though, it seems to stain nearly as easily. at least in my experience.