Mora Knife Oxidation

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artmcclure
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Mora Knife Oxidation

Post by artmcclure »

I went saltwater fishing about a week ago, but I took the wrong knife with me. I thought the blade was SS, but it had a CV blade. It was only in the water for about 5 minutes; it did not rust. But it developed a spotty grayish white haze on both sides of the blade. Is there an east way to remove the haze? Or should I just start polishing?
Art McClure
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Sharpnshinyknives
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Re: Mora Knife Oxidation

Post by Sharpnshinyknives »

artmcclure wrote:I went saltwater fishing about a week ago, but I took the wrong knife with me. I thought the blade was SS, but it had a CV blade. It was only in the water for about 5 minutes; it did not rust. But it developed a spotty grayish white haze on both sides of the blade. Is there an east way to remove the haze? Or should I just start polishing?
Boy Art, That’s a good question. Hopefully someone who has had experience will come along w/ a good solution. I personally would try using a polishing compound first and if that doesn’t take it off then I would move up to a polish. What I use is Machine Polishes 1 thru 4 from Griot’s Garage. It’s for clear coat paint on cars so it’s not an aggressive polish. It works well by hand or by machine. I also have the orbital polisher by Griot’s, it is designed not to burn through clear coat so you can’t get too aggressive with it. I have it gently mounted to a vice and use it that way.
My only concern w/ what happened to the knife is to make sure that you have arrested the chemical reaction that was started on the metal. Not sure if flushing w/ just water will do that or if there is something someone can recommend to make sure that this is neutralized. If you have 2 dissimilar metals on that knife, you could still have some major corrosion problems down the road. I will try to study on this and see if I can find an answer to how to neutralize that galvinic reaction. If I find an answer, I will post it here.
SSk Mark “Freedom is never more than one generation away from extinction. We didn't pass it to our children in the bloodstream. It must be fought for, protected, and handed on for them to do the same.” Ronald Reagan
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Sharpnshinyknives
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Re: Mora Knife Oxidation

Post by Sharpnshinyknives »

From what I have read, potash or soda would neutralize the chemical reaction. I have seen this discussed on here before. Make a paste out of baking soda and scrub the knife with it and really get it in there where the salt water might have soaked in. I would be tempted to leave it in a bath of this for a few hours and dry it with compressed air and then polish it after you do that. Hope this helps.
SSk Mark “Freedom is never more than one generation away from extinction. We didn't pass it to our children in the bloodstream. It must be fought for, protected, and handed on for them to do the same.” Ronald Reagan
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Re: Mora Knife Oxidation

Post by kootenay joe »

Sounds like a 'patina' which is oxidation of just the very surface of the blade. Not harmful, in fact it helps to protect from actual rust develping.
I would just keep using it and see what happens. If you need to replace it ever it's only $15-$20 for the basic non stainless Mora'.
kj
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cody6268
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Re: Mora Knife Oxidation

Post by cody6268 »

kootenay joe wrote:Sounds like a 'patina' which is oxidation of just the very surface of the blade. Not harmful, in fact it helps to protect from actual rust develping.
I would just keep using it and see what happens. If you need to replace it ever it's only $15-$20 for the basic non stainless Mora'.
kj
Agreed. Accidentally left some stuff (presumably plant matter from cutting brush) on one of my Basics, and it rusted. Cleaned the rust off, and it left the same patina. I personally have noticed darkened, aged carbon steel knives tend to rust a lot less. Moras themselves seem to be less prone to rust than other carbon steels.
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tongueriver
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Re: Mora Knife Oxidation

Post by tongueriver »

cody6268 wrote:
kootenay joe wrote:Sounds like a 'patina' which is oxidation of just the very surface of the blade. Not harmful, in fact it helps to protect from actual rust develping.
I would just keep using it and see what happens. If you need to replace it ever it's only $15-$20 for the basic non stainless Mora'.
kj
Agreed. Accidentally left some stuff (presumably plant matter from cutting brush) on one of my Basics, and it rusted. Cleaned the rust off, and it left the same patina. I personally have noticed darkened, aged carbon steel knives tend to rust a lot less. Moras themselves seem to be less prone to rust than other carbon steels.
Agreed. Leave it. BTW, I bought three of them recently for $8 each, shipped.
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artmcclure
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Re: Mora Knife Oxidation

Post by artmcclure »

Thanks all! I'll leave it alone. It's got a story.
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Re: Mora Knife Oxidation

Post by JACK OF ALL TIRADES »

I took my new one to a clambake and used it. I also sliced up multi racks of ribs after seeing a girl struggle and right quick. I have that patina going on. It was dull but came back at least as good as new which shocked me.
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