oil beading up on new mora knife`s

J

John Stubley

Joined
May 25, 2017
Messages
131
Hi.

I bought a couple of the pro mora knives, one with a carbon blade and one with an stainless steel blade, I also bought an anglo arms knife and the oil does not bead up on that knife.

I used 3in1 oil and rubbed it thickly into the blades and left it for a couple of hours, when i checked the oil was beaded up.

Is this just excess oil, and just needs wiping off.

Thanks

John.
 
Not sure I'd use 3in1 for that since it tends to gum but there's lots of ideas on which oil is best.
Mineral oil when needed is a pretty popular choice.

Did you oil the stainless blade too?
 
Yeah, I oiled both, SS can corrode as well it just takes a lot more.

I saw an knife rust prevention video on youtube, they tested 10 different products in an 21 day outdoor test on knife blanks, mineral oil came around 6th place loads of rust, wd40 came 2nd place, 3in1 oil came first with almost no rust marks at all.

John.
 
John Stubley said:
If you are using the knife to cut something you are going to eat, food grade mineral oil is recommended.

John.
Click to expand...

Yes it is. Hopefully you are not preparing food with your 3 in 1 knife.

So, why are you so worried about rust? While I do put some mineral oil on my carbon steel blades for storage, while actually using a knife, wiping the blade (stainless or carbon) off after use really takes care of the rust problem entirely.
 
John Stubley said:
Yeah, I oiled both, SS can corrode as well it just takes a lot more.

I saw an knife rust prevention video on youtube, they tested 10 different products in an 21 day outdoor test on knife blanks, mineral oil came around 6th place loads of rust, wd40 came 2nd place, 3in1 oil came first with almost no rust marks at all.

John.
Click to expand...

I've had my O1-bladed Bushfinger out in the woods for over 21 days the past winter (not in a row), the only time it rusted was when I let it, all you really have to do is wipe excess moisture-trapping debris off your blade when you're done using it or when you're ready to store it and put it in a dry sheath and you shouldn't have to worry about rust at all.
 
John Stubley said:
Yeah, I oiled both, SS can corrode as well it just takes a lot more.

I saw an knife rust prevention video on youtube, they tested 10 different products in an 21 day outdoor test on knife blanks, mineral oil came around 6th place loads of rust, wd40 came 2nd place, 3in1 oil came first with almost no rust marks at all.

John.
Click to expand...

Are you planning on leaving your knives wet for 21 days? Wipe them off after use and they won't rust. I'd be incredibly surprised to see a stainless Mora develop rust with that high polish they put on it. If the carbon one rusts, it's easy to fix. These are tools, not display pieces. Wipe them dry after use. If the carbon is going into storage for a while, a thin layer of USP mineral oil is sufficient to inhibit corrosion unless it's left in a very humid environment.
 
I checked my knives this morning after wiping the oil off last night, now there appears to be dark circles on both the SS and Carbon knife like water marks, I just wonder if the blade has taken the oil, or should i clean them both with solvent and appy the oil again.

Thanks

John.

PS. below is a link to a photo of the knife blanks at the end of the corrosion test.

1095 Steel, Corrosion_Rust Test for Knife Makers - YouTube
http://imgur.com/Fr63ikV
 
Why don't you force a patina on the one with carbon steel? I'm not saying you won't have to wipe it down after use, but it'll help.
Plus, I prefer the look.
 
Metal doesn't absorb oil. Oil can, however, adhere to the surface of metal.

The extent to which a liquid beads up on a surface is related to the surface tension of the liquid, and the flatness of the surface. Maximum beading for any given liquid occurs when the surface is completely flat, i.e, when the contact angle between the the liquid and the flat surface is 180 degrees.

If the surface is uneven, the liquid will spread out further as it fills in all of the little nooks and crannies, as the capillary effect adds to the gravitational pull trying to flatten the liquid out, which is resisted by the surface tension of the liquid trying to form a sphere with minimal surface area.

So a mirror finished piece of metal will allow oil (or water) to bead up, and a matte or textured finish will result in it spreading out more and adhering to the surface better.

Go look at the picture of the Mora Pro S knife here:
https://morakniv.se/en/product/pro-s/

They show it with water beaded up on it. Oil will do the same thing.

I have no idea which of the many Anglo Arms knives you bought, but if it has a matte or coated finish, that would explain why oil forms a thinner surface on it.

Or did you not come here to discuss physics?



*Edit - I quite likely don't know what I am talking about with respect to parkerization, so I removed the paragraph where I mentioned it.
 
Last edited:
jbmonkey said:
op you are overthinking it. just keep them dry and clean and use 'em. you'll be fine. little bit of rust polishes right off quickly and easily. use the knives and enjoy them......
Click to expand...


I have to agree with this^^^^

Too many people pay too much attention to these youtube "tests" that are un-realistic. Are you going to leave your knife in a wet sheath for 21 days, or laying out on the lawn with the sparkler system running?

Just use the knife and keep it clean. In time it will develop a nice gray patina that will give a measure of protection. Just wipe the knife off when your done. Look at it this way; The old Vikings set sail in open boats in salt water environments and no problem withthier weapons and tools rusting. They just wiped them down now and then. The old explorers and mountain men, Roman Legionaries and Crusaders all kept their carbon steel tools in good condition under very primitive conditions.

People have got spoiled by the modern stainless steels and over think taking care of the old carbon steel. In truth, it doesn't take a lot of care.
 
jc57 said:
Metal doesn't absorb oil. Oil can, however, adhere to the surface of metal. ...

Or did you not come here to discuss physics?
Click to expand...

^And this. A blade doesn't "take" oil....it is merely coated by the oil. I believe it adsorbs the oil, does it not jc57 jc57 ?

I'll talk physics!

Heck, if I can't get some of the "convex" folks to accept that mathematics exists, might as well try physics!
 
Yes, adsorption is the appropriate specific term for adhesion of a liquid (or gas) to a solid surface. Adhesion is a broader term, my bad.

There is a surprisingly good discussion of the topic on Wikipedia under the "wetness" topic.

But rather than get into the science of it - anyone who has lived on the planet for a while should have at least casually observed that water beads up on clean polished surfaces but tends to spread out on matte or rough surfaces, depending on where the surface substance falls on the hydrophilic-hydrophobic spectrum. Observe the difference in a clean and waxed vs dirty car when it rains.

You can, of course, modify the adsorption of a surface by changing the surface material. For example - spray Scotchgard on a fabric and watch water bead up, even though it is still a rough surface. Or conversely, use a surfactant (like soap) to make a liquid "wetter." My belief is that one of the reasons a patina can be effective in preventing rust is that it provides a better surface for adsorption for oil, similar to parkerization but at a much finer level of "fuzziness." You are changing both the surface texture, as well as the surface material, coating it with black iron oxide.
 
You must log in or register to reply here.
Back
Top