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Questions on "forced patina"

Posted: Thu Jan 19, 2012 2:42 pm
by Jigslinger
I attempted for the first time a forced patina on an old jackknife using white vinegar. Overall I am pleased with the result but a couple questions. What effect, if any, does leaving the blade in the vinegar longer or shorter times? What actually causes the patina? Is it permanent or can it be polished off? What advice for the next time? One thing I did learn was to mask the areas of the knife you don't wish to change, like the bolsters, springs, and liners. Even the vinegar in the air can discolor those areas. Polishes off the nickel but masking would save some work. Thanks.

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 4:54 pm
by SHAMAN
I have a related question. I collect older knives and have three (Rem Bullet Trapper, XX Toothpick and Tested Coke Bottle Hunter) that are really nice except someone polished the blades. Any ideas on how to dull the shine. I heard cut an apple.

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 5:03 pm
by Owd Wullie
If ya want it darker and to go faster, boil the vinegar and put the knife blade in the hot vinegar.

Best way is to get a cup and pour the vinegar into the cup up to the area where you do NOT want the hot vinegar to get to. Stand the knife point down in the cup. Then boil your vinegar, pour it back in the cup and put the knife blade into the vinegar. Check it every minute or so until you have it where you like it.

Clean the blade with hot soapy water and then finish with alcohol or acetone before you start. Dry it and oil it after.

You can turn it nearly black pretty quick that way.

Or, just use it. :)

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 5:54 pm
by Joe Dirt
Here's a some what controlled method. I was informed that apples contain malic acid, so this is
basically the same result you will get from peeling an apple every day for about 2 months.

The blade on this knife was almost mirror polished and didn't look to good with all the pitting.
After 2 weeks of intentionally peeling "an apple a day" I stuck it in an apple overnight and this is the
result from approx. 8 hours.
Yes, your going to have a sticky knife but as Willie said, just give it a good wash and then dry & oil.

And yes, the patina can be polished back off.
I'm no scientist but I believe the patina is iron phosphate. (someone PLEASE correct me!)

Let's see your results - whatever method you use!

...... Joe

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 6:05 pm
by SHAMAN
Thanks Joe Dirt....I'm gonna try that. Think I'll polish a POS and expirament first

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 7:36 pm
by MikeEngland
SHAMAN wrote:Thanks Joe Dirt....I'm gonna try that. Think I'll polish a POS and expirament first
GOOD IDEA. I tried to force patina several times, and you don't always get a consistant result. I tried first on a knife that I liked and was not happy with the way it turned out. I also met a member who suggested applying yellow mustard to the blade. I tried it and it worked out pretty nicely.

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 7:49 pm
by FRJ
As a woodworker, I learned in "FineWoodworking" to put iron screws and/or bolts and anything iron,even rusty iron, in white vinigar and leave it for a good while. (weeks?) Covered. Strain it through a clean cloth and you will have a fine black dye for hardwoods.

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 9:11 pm
by Joe Dirt
Interesting, Joe!
That would be a black oxide dye, wouldn't it? ::shrug::

...... Joe

Re: Questions on "forced patina"

Posted: Thu Jan 19, 2012 11:45 pm
by chetr1200c
i eat and i peel my apples every day. always with a sharp folder. but i only use stainless 440.
i did use carbon steel once and noticed the new blade and also the unused blade was really tarnished and starting to rust since i didn't get a chance to clean the blades too good because me and the dogs were out on our daily hikes. and now because of that, i haven't used anything but stainless. tomatoes work just as good for forced patina.

Re: Questions on "forced patina"

Posted: Fri Jan 20, 2012 12:08 am
by tjmurphy
I'm trying to figure out why you would want to chemically force a patina on a knife blade?? ::shrug:: If you use the knife it will come along naturally. And, most of the forced patina that I've seen are not very attractive. JMO

Re: Questions on "forced patina"

Posted: Fri Jan 20, 2012 1:54 am
by Paladin
tjmurphy wrote:I'm trying to figure out why you would want to chemically force a patina on a knife blade?? ::shrug:: If you use the knife it will come along naturally. And, most of the forced patina that I've seen are not very attractive. JMO
Right on Murph. I have never figured it out either. Different strokes for different folks, I guess! :D :D ::shrug::

Re: Questions on "forced patina"

Posted: Fri Jan 20, 2012 9:04 am
by orvet
I have a Case Swayback Jack with CV steel. I was using it and allowing it to patina normally when less than two weeks after I got it I notice rust spots developing on the blade. That is the reason I forced the patina on that knife. I actually used cold bluing for the patina so that it would be heavier than that created by the acids in fruit. The whole purpose was to prevent rust and protect the metal, (the reason guns were blued in the first place), and not for looks.

Re: Questions on "forced patina"

Posted: Fri Jan 20, 2012 11:21 am
by Elvis
Here are a couple of Case CV knives and the yellow handled Sodbuster was treated with Gun Bluing Compound as soon as I bought it. While Pappy always said to oil your guns after using them, I've found that a good coat of Ren Wax seals the bluing very well, so only the hinge pin gets oiled now, The Sodbuster is about 5 or 6 years old. It's not the only way to get a patina. Just the one I've grown to prefer.

Image

Re: Questions on "forced patina"

Posted: Fri Jan 20, 2012 11:23 am
by big monk
I feel the same way,as Dale,about the Case CV Steel____I too,was using my first "'CV Case Knife"" (before I knew,there were different steels ::dang:: ) and noticed it spotted up like a leopard??? When I tried to clean the knife, ::hmm:: found out it was rust ?? _____ All my EDC's now,are the 1095 carbon,and I'll polish & clean them,with Mothers Mag & Aluminum Polish, about once a month,to keep the ""Leopard Spots"" off of em' ::nod:: ---like Ray said,"'Different Strokes"" ::tu::

Re: Questions on "forced patina"

Posted: Fri Jan 20, 2012 11:53 am
by Ramrod
orvet wrote:I have a Case Swayback Jack with CV steel. I was using it and allowing it to patina normally when less than two weeks after I got it I notice rust spots developing on the blade. That is the reason I forced the patina on that knife. I actually used cold bluing for the patina so that it would be heavier than that created by the acids in fruit. The whole purpose was to prevent rust and protect the metal, (the reason guns were blued in the first place), and not for looks.
Exactly!
I tend to sweat alot at work, and my knives develop some rust within one good hard day. But, not if I get a good protective coating in Vinegar (or Coke) first.
The key to getting it even and consistant is to get ALL oil and residue off the blades before you even start. I take an old toothbrush with Dawn dishsoap and water, then blow dry with compressor.
I can still polish it off if I want, but in the meantime......it doesnt rust!!
Mark

Re: Questions on "forced patina"

Posted: Fri Jan 20, 2012 3:51 pm
by Jigslinger
tjmurphy wrote:I'm trying to figure out why you would want to chemically force a patina on a knife blade?? ::shrug:: If you use the knife it will come along naturally. And, most of the forced patina that I've seen are not very attractive. JMO
Well, one of the reasons is I'm a curious person and I wanted to check it out. Secondly, the knife in question is an really old bareheaded jackknife I bought off ebay. Someone had buffed the blades and 1) they were too shiny given the antique look of the knife, and 2) there were faint vertical buff marks on the blade I wanted to cover up. After hand rubbing the blades and removing a good deal of the patina, I am very satisfied with the overall look of the knife. She has a keen edge now and is currently in the EDC rotation. Probably won't do it again unless a similar situation comes up.

Re: Questions on "forced patina"

Posted: Sat Jan 21, 2012 3:55 am
by oldgoat1911
Every body is correct on methods...I like to help some of my carbon blades too. The only thing I have done differently was to polish with Flitz after treatment. Sometimes you can get some great results from repeating patina applications with the polish in between. It truly does protect if you oil at the end...Herb