Erasing the patina

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If I get actual rust, I keep a little peice of 600 grit sand paper near the sink and give the blade a quick scrub.
 
I find green ScotchBrite does OK at removing the top layers, but without a chemical to mildly etch it out it can only do so much. BKF is a gentle-enough acid, with a gentle-enough abrasive to do a wonderful job.
 
The ScotchBrite I use is the coarse one, color mauve/brown. I must agree not the deepest patina is being removed, but have never wanted to do so.
 
Concentrated nitric acid. It'll get that nasty patina ALL the way off!
 
After the acid, you may want to neutralize. Baking Soda should do the trick...
 
I use some Autosol or Flitz on a rag if I want to remove/reduce patina.
 
Thanks for all the suggestions everyone!

I heard that some stuff can actually scratch the blade or mess up the finish somehow. Which ones should I be aware of, and any other tips as to not cause myself grief?
 
I just tried using Steel Glo. Not much patina on my knives, but had some light rusty bits and this did very well. Bought this a few years ago in Malaysia and forgot about it, but obviously still works. It's a US product so should be available for you. Also it claims to be non-toxic which is a plus.

http://www.agelong.com/v/vspfiles/photos/03655-2T.jpg
 
Thanks for all the suggestions everyone!

I heard that some stuff can actually scratch the blade or mess up the finish somehow. Which ones should I be aware of, and any other tips as to not cause myself grief?

I would start with BKF on the end of a wine cork or a metal polish like Flitz, Metal-Glo or Nevr-Dull wadding. ScotchBrite, both the green and brown, may put fine scratches on a blade, at least in my experience.
 
Patina cleaning test

I was curious enough to do a short test of the three methods that were suggested: BKF with a cork, BKF with a ScotchBrite pad and a metal polish, in this case Metal-Glo.

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The sacrificial lamb was a Harner O1 cleaver. This is how it looked pre-test:

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I soaked a paper towel in vinegar and laid it on the blade for five minutes. Instant patina.

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Then I cleaned three swaths, from top to bottom, Metal-Glo on a paper towel; BKF on a wine cork; BKF with a new ScotchBrite pad.

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I was a bit surprised to see that the metal polish did the best job. The fine scratch pattern that the ScotchBrite pad left is easily seen.

Rick
 
Rick, this is more than I could ever ask for in a reply. Thanks so much!

Certainly the scratches are very visible. I was always hesitant using scotch brites, because if makers use them to create a finish, than using one to clean up a knife would certainly alter the finish, wouldn't it? Maybe it's a certain type of scotch brite, or technique, or something.

That metal polish looks fantastic, and I'll have to go get some.
 
I find a good tooth paste works well, make sure it's a paste and not gel. a smokers toothpaste has a little extra grit. put a little bit on a towels and rub away.
 
+1 I thought I was the only one using toothpaste works great

I find a good tooth paste works well, make sure it's a paste and not gel. a smokers toothpaste has a little extra grit. put a little bit on a towels and rub away.
 
I actually use plane whit vinager if I get small rust spots. As far as patina goes I haven't removed one, patina on my Yoshihiro is getting pretty deep and not so pleasing. Never though of tooth paste. I was thinking i would need a finger stone to repolish things. Thanks for this thread.
 
This is a great thread. Thanks for taking it the extra mile Rick.
I'm on the BKF/Flitz tip. I find the Scotch-Brite too abrasive, no matter the grit. It even leaves tiny scratches on my stainless Henckels. Also, a little Chromium Oxide on the buffing wheel(gotta be careful though) will shine it up like a champ!
 
Pensacola Tiger (or anyone else with scratches) - now that you have those ScotchBrite scratches on your blade, what is your method of removing them - ie. polishing off the scratches?
 
I find the Scotch-Brite too abrasive, no matter the grit. It even leaves tiny scratches on my stainless Henckels.
Yep. I use the green ScotchBrite side of regular kitchen sponges on my extremely-reactive Sab paring knife, which is well pitted and scratched anyway. After hulling just a couple of pints of strawberries it will take on a deep -- almost black -- patch across the middle, which is less than pleasing to the eye.
 
Pensacola Tiger (or anyone else with scratches) - now that you have those ScotchBrite scratches on your blade, what is your method of removing them - ie. polishing off the scratches?

I don't know about anyone else, but hand-rubbing with wet/dry 3M paper backed with something with 'give' is the way I go. Don't use a hard block, because it won't conform to the surface and you'll just polish the high spots. For scratches like those I put on the Harner, I'll start with 400, then move to 800 and finish some MetalGlo.
 
I had some time this morning, so I tried toothpaste on the stripe of patina between the area cleaned at the top with Metal-Glo and the area cleaned with BKF and a cork. Toothpaste may work on light patina, but it didn't do a great job this time. YMMV.

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