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jackknifeh
05-20-2011, 06:10 AM
Hey guys,

I read an article in Blade magazine where some people speed up forming patina on knife blades by sticking the blade into a potato and leaving it overnight, coating it with mayonaise, and other ways involving food. In addition to changing the appearance of the steel it supposedly creates a corrosion barrier on the steel preventing another kind of oxidation (rust).

I've been thinking about this since I now have an M4 steel blade. I've read where M4 isn't stainless but it's not a pure carbon steel either. Has anyone ever tried to speed up the patina process? Does patina prevent corrosion? That is really what I'm wanting but I also like the look also. Any info or advice is appreciated.

Jack

tonydahose
05-20-2011, 09:11 AM
i believe the patina will help prevent any further oxidation from happening beneath the patina i.e.. rust. at least that is how i think it works:rolleyes:. i have read mustard and pickle juice can be used to force a patina.

2cha
05-20-2011, 09:30 AM
I bought some cold blue to try out and plan to use it on one of the super blue mules. When I get around to it, I'll let you know.

Zoldner
05-20-2011, 09:41 AM
I put a patina on an opinel pretty easily using some vinegar. It doesn't take too long to get a dark finish.

The Deacon
05-20-2011, 09:44 AM
i believe the patina will help prevent any further oxidation from happening beneath the patina i.e.. rust. at least that is how i think it works:rolleyes:. i have read mustard and pickle juice can be used to force a patina.Help is the key word Tony. As with bluing on firearms, a well done patina will increase a blade's resistance to rust, but it's not a panacea. You still have to take more precautions than with a good stainless steel, or the item in question will rust, just as most stainless will rust if you neglect it badly enough.

jossta
05-20-2011, 09:53 AM
Yeah, I haven't done it to my Bradley yet, but from what I've heard it only helps, and apple cider vinegar will take care of it for you...

DeathBySnooSnoo
05-20-2011, 11:51 AM
I think that there is a thread where there aer pics of forced patinas on a GB...

gunnut35
05-20-2011, 01:08 PM
Mustard works really well.

rosconey
05-20-2011, 02:09 PM
bought some new kitchen cutlery that said super stainless-stuff colored over a second after it touched mustard-was supposed to be german steel:mad:

phillipsted
05-20-2011, 02:51 PM
Here's the thread from dbcad about the patina on a Super Blue Mule.

TedP

http://www.spyderco.com/forums/showthread.php?t=48201

DMgangl
05-20-2011, 05:06 PM
Like this?
http://i78.photobucket.com/albums/j94/dm_gangl/DSC02417.jpg

Use Mustard. There are several advantages to using mustard. Since its thick its easier to use on the blade without getting any on the edge which will dull the knife. You also get different colors which IMO is nicer looking then strait vinegar, which will just give you a dark grey/black. When you put the mustard on let it dry before removing it, this will give you the best results.

For the blade in the pic. I soaked the blade for about 6 hours in a vinegar soaked rag. The problem was the vinegar pooled in some areas were you see the dark spots. Also since I didn't have anything on the top the other side of the blade pushing the rag down that side wasn't as dark. To cover it up and just to experiment I did stripes of mustard.

If I were to do it again I would just use mustard cover the edge in a thin/meduim layer if mustard and let it dry.

DM

Evil D
05-20-2011, 05:55 PM
I've been tempted to try this with my Caly 3, just to see if i could get the ZDP layer to patina and leave the 420J2 part polished. I think it would work since the 420J2 is a lot more stainless.

jackknifeh
05-21-2011, 07:02 AM
Like this?
http://i78.photobucket.com/albums/j94/dm_gangl/DSC02417.jpg

Use Mustard. There are several advantages to using mustard. Since its thick its easier to use on the blade without getting any on the edge which will dull the knife. You also get different colors which IMO is nicer looking then strait vinegar, which will just give you a dark grey/black. When you put the mustard on let it dry before removing it, this will give you the best results.

For the blade in the pic. I soaked the blade for about 6 hours in a vinegar soaked rag. The problem was the vinegar pooled in some areas were you see the dark spots. Also since I didn't have anything on the top the other side of the blade pushing the rag down that side wasn't as dark. To cover it up and just to experiment I did stripes of mustard.

If I were to do it again I would just use mustard cover the edge in a thin/meduim layer if mustard and let it dry.

DM

I covered my M4 blade with mustard for about 4 hours last night. It left a very consistant change in color where the mustard was. There is a difference in color close to the handle where there wasn't any mustard. The edge was dull to the point it wouldn't slice paper cleanly but a little stropping took care of that. I'm probably going to do it again tonight to get a little darker color. I've also thought about taking the blade out and getting a patina around the pivot area also. If patina helps to prevent rust I was thinking the inside of the knife would be a good place to have patina. Has anyone ever done this and if so, were there any negative side effects to performance (stiff in opening or closing, etc.)? I really want this knife to last (Manix2 w/M4). I wasn't aware I would be as concerned about long term corrosion as I am since M4 isn't a stainless steel. This is my first non stainless steel knife. I keep all my knives and tools oiled as needed so I may be overly concerned for no reason.

Jack
Edit: I like the look of your GB blade and I think I'll try to put a pattern of some kind. Stripes or something.

Evil D
05-21-2011, 08:08 AM
On most knives i would think that patina like the GB just looks filthy and neglected, but it looks damn good with the carbon fiber. Are you guys taking them apart and doing the pivot areas too? I would be concerned about rust there more so than on the blade.

Creepo
05-21-2011, 01:59 PM
First of all patina, corrosion and rust.
Oxidation can form as spots that with longer exposures lead to pitting, tiny black holes where the oxidation reaches deeper in the material. Getting rid of pitting is tricky and it can spread once the reaction has started. Then theres the uniform oxidation layer referred to as patina.
For more oxidation to happen oxygen is needed to be in contact with the material, when there is an even coating of oxidation, the oxygen can't get in direct contact with the metal. Through diffusion it will still seep through the layer but this is VERY slow compared to direct contact. The layer of patina will thicken slightly over long periods of time (darker color) and exposure to corrosive substances but deep pitting won't form, at least easily. ;)

Now for the pivot, I highly doubt the action will be as smooth as it was without patina. The smoother and polished the tang area, the smoother the action. With the patina I'm sure you can still achieve a reasonably smooth opening if you wear it down a bit but it won't be as smooth. :(
Where the washers and lock are in contact with the tang the oxidation will also wear down, perhaps completely. If you force a patina in the tang I would recommend you polish the patina off from the washer, pivot hole and lock travel surface area. Just keep the pivot oiled after this and it'll be fine, thicker better oils will stick there longer so invest in a good lube. :)

toomzz
05-21-2011, 02:15 PM
Hi, I did some forcing on my two GB's as well. With mustard, my own blood (when I cut myself accidentally) and Birchwood gun blue (see picture). That last option worked well, but by using the knife the effect wears off. Since there is a death-head on the package of the Birchwood I don't wanna use it for foodprep anymore, so I removed the patina and stopped using it.

I never left a Spydie overnight in mustard, a patato etc. I learned my lesson when leaving a lemon on a antique (Gunto) japanse katana for a few hours. Ouch....it left a permanent mark.....

Beware of sudden popping up black pits. Oil that M4 once in while, especially when you do forcing patina's!

Tomas

gunnut35
05-21-2011, 09:57 PM
Here is a example of using mustard to force a patina.
This one is a #9 opinel that i use everyday in my kitchen and i cant remember when i did it.
http://i87.photobucket.com/albums/k134/spaceweaseal/a211.jpg

This is another #9 that i just did. Just put the mustard in whatever pattern you want.
http://i87.photobucket.com/albums/k134/spaceweaseal/a201.jpg
http://i87.photobucket.com/albums/k134/spaceweaseal/a200.jpg
I only leave the mustard on for 15-20 minutes and the rinse with water. The longer you leave it on the darker and wider the lines will be. The outer edges of the mustard forms the lines.
http://i87.photobucket.com/albums/k134/spaceweaseal/a205.jpg
http://i87.photobucket.com/albums/k134/spaceweaseal/a209.jpg

You then can add a little mustard to a paper towel and lightly coat the blade to darken then wipe off. Then i put mustard drops all over the blade for about 10min and rinse. The end result will be a cool effect that gives it almost a anodized color to it.
Sorry for the poor quality of my pictures.

DeathBySnooSnoo
05-22-2011, 12:33 AM
That is a pretty awesome effect! Looks really great...

gunnut35
05-22-2011, 12:43 AM
That is a pretty awesome effect! Looks really great...

The key is to lower the time on each coat of mustard, that way it gives it depth and color instead of just gray lines.

jackknifeh
05-22-2011, 06:03 AM
Great info on forcing patina. The first thing I did was put the blade in a potato for a few hours with some but little effect. Then I tried vinegar. Again, little effect. Then I used mustard and that made a bigger difference than the others. The edge was a little dull so I stropped it to get the edge sharp and bevel shiny again. Then I used mustard again trying not to get any on the very edge. Some mustard did get on the bevel though. As soon as the mustard was dry I washed it off. There were 5 small pits on the bevel like Toomzz mentioned. I was able to remove the darkness inside the pit that I assume would have turned to rust and further damage.

Then I remembered that I always coat knife blades with Tuf-Glide. When I started with the potato the entire blade was treated including the edge. I am thinking the Tuf-Glide prevented patina from forming as fast as it would without it. I say this because after I stropped the edge and bevel I assume there was no Tuf-Glide there. Tuf-Glide advertises that it can't be washed off but I'm sure sharpening/stropping does remove it since that is removing steel. Then the pits formed because the mustard was on bare steel. Since my goal was to prevent corrosion with a little patina I think my goal has been satisfied. I would love to try creating the beautiful designs that Gunnut35 did but if I do that it will be on other knives first. I have a consistant change in color on the blade except for the tang/pivot area. I'll leave the inside area of the blade alone like Creepo suggests. I'll just keep it oiled properly.

I appreciate all the info you guys provided.

Thanks,
Jack

toomzz
05-22-2011, 06:27 AM
Cool-cool-cool Gunnut! Love it!

:cool:

VashHash
05-22-2011, 06:25 PM
I need to get some mustard for my 1075 condor golok. Love those designs from the mustard. It kinda matches that brocade fabric you used as the background. I figure I try it on a $40 machete before I use it on the M4 millie. I wanted to get some on the way home but I forgot

jackknifeh
05-23-2011, 06:56 AM
How long has it taken patina to form on your blade using mustard. I say mustard because it worked faster than the other things I tried. I tried it on M4 steel. I'm asking because I've left mustard on the blade for up to 2-3 hours and a couple of other times I washed it off as soon as it appeared to have dried, maybe 30 minutes max. The amount of time I've had something on the blade seems like a very long time to me to get the results I've seen in the pictures in this thread (which really look great). I coated my blade with Tuf-Glide as soon as I got it and applied it a couple of times after that also. What I want to know is did the Tuf-Glide protect the blade from a patina forming or have my results been normal? I really would like to know this because I'm not only interested in patina but also the performance of the Tuf-Glide. If I had two pieces of non-stainless steel I'd do a comparison but I don't. Thanks.

Jack

VashHash
05-23-2011, 07:03 AM
I found it took about 30 mins for the patine to form. After that its just hard to clean off but you have to use a thin layer of mustard so it can get oxygen to the steel and oxidize. Its actually the vinegar in the mustard that really does it but the mustard makes a vinegar paste instead of liquid so its more managable. I've done it a few times and I'm liking the patterns but I need to do it some more. Tuf glide will most definitely stop the patina. I advise you wash the knife in warm soapy water then clean it really well with alcohol to get bare steel. Some others say to scuff the metal slightly so the acid can etch it easier. Either way it seems to be working on my machete. Just needs a few more applications so I get a strong pattern. Then I'll try darkening it up some to make it stand out more

jossta
05-23-2011, 07:12 AM
I think the Bradley fell out of my pocket this weekend in a cab, but I haven't given up on finding it yet. If I do, I think I see some mustard in it's future.

Although, it is usually the one I carry if I think there's a chance I could misplace it since it's the only one that's not a Sprint or discontinued. I think my mistake was unclipping it and just letting it ride in the pocket.

jackknifeh
05-23-2011, 07:24 AM
I found it took about 30 mins for the patine to form. After that its just hard to clean off but you have to use a thin layer of mustard so it can get oxygen to the steel and oxidize. Its actually the vinegar in the mustard that really does it but the mustard makes a vinegar paste instead of liquid so its more managable. I've done it a few times and I'm liking the patterns but I need to do it some more. Tuf glide will most definitely stop the patina. I advise you wash the knife in warm soapy water then clean it really well with alcohol to get bare steel. Some others say to scuff the metal slightly so the acid can etch it easier. Either way it seems to be working on my machete. Just needs a few more applications so I get a strong pattern. Then I'll try darkening it up some to make it stand out more

Thank you. What you said confirms what I was thinking and hoping. I hoped my using Tuf-Glide was doing some good and believed it was but now I think that has been confirmed. If I can't cause corrosion intentionally after using Tuf-Glide then I can be confident it will protect the steel under normal every day use, even inside the pivot area which I saturate with it on any new knife, then about once a year after that. I recently used Quick Release on one Delica because using Tuf-Glide the lubrication feature only lasted about 2 weeks, then there was a tiny feeling of no lubrication. The Quick Release seems to keep the lubrication longer and it also claims to have similar corrosion protection by bonding to the metal instead of just providing a wet layer of oil like oils that have been around forever (WD-40, 3-in-one, etc.). I'm not knocking the oldies, they have been around forever because they work for what they were designed for. But with technology new and improved products seem to be available now.

Jack

jackknifeh
05-23-2011, 07:27 AM
I think the Bradley fell out of my pocket this weekend in a cab, but I haven't given up on finding it yet. If I do, I think I see some mustard in it's future.

Although, it is usually the one I carry if I think there's a chance I could misplace it since it's the only one that's not a Sprint or discontinued. I think my mistake was unclipping it and just letting it ride in the pocket.

Hope you find your GB. I'm sure the driver will turn it in if you dropped it in a cab. Now if I had been the driver I'd have a new knife. :D Just kidding I think. :confused:

Jack

jossta
05-23-2011, 07:31 AM
Hope you find your GB. I'm sure the driver will turn it in if you dropped it in a cab. Now if I had been the driver I'd have a new knife. :D Just kidding I think. :confused:

Jack

Yeah, I just have to figure out which cab company, lol. Going to try calling some places during lunch today.

jackknifeh
05-23-2011, 07:42 AM
Yeah, I just have to figure out which cab company, lol. Going to try calling some places during lunch today.

I lost my wedding ring once. Now I know a wedding ring isn't nearly as important as a knife :) but I did get it back through a series of events that are only just short of miraculous. I'm sure you'll get your knife back. My son recently misplaced his Delica and got it back so you are in good finding lost things company. :D

Jack

jossta
05-23-2011, 09:31 AM
Good to hear. That's how I usually am too, but not so sure about this one though. Fingers crossed...

Saralach
05-23-2011, 01:07 PM
Has anyone tried a patina on the stainless handled knives? Both the handle and blade? Curious if that works.

The Deacon
05-23-2011, 03:22 PM
Has anyone tried a patina on the stainless handled knives? Both the handle and blade? Curious if that works.AFAIK, you can't really force a patina on stainless steel. Some stainless blades may discolor a bit, but to nowhere near the extent a carbon steel would. Know solid ZDP-189 will darken somewhat. On the other hand, the stainless steel that Spyderco uses for handles is very rust resistant, so I doubt you'd see any change at all.

Saralach
05-23-2011, 03:58 PM
Someone on the CS forums posted a video for a patina on SS using sulfamic acid crystals made into a paste. Going to try foods first. I'm patient and have more than enough knives to rotate EDC.

jossta
05-25-2011, 09:39 AM
I'm sure you'll get your knife back. My son recently misplaced his Delica and got it back so you are in good finding lost things company. :D

Jack

FOUND it. Thanks for the confidence :D.

jackknifeh
05-25-2011, 11:06 AM
FOUND it. Thanks for the confidence :D.

Glad to hear it. Do you have an honest cab driver to thank or was it somewhere else?

Jack

jossta
05-25-2011, 11:10 AM
Fell out in a friends car before the cab. Going to pick it back up today, maybe play with some mustard.

Senate
05-26-2011, 12:06 PM
apples work great and fast too.

SkullBouncer
06-05-2011, 09:51 AM
Thanx for the info here, esp. gunnut.

This thread earlier motivated me to work a patina into brass and copper -- I as well collect brass sculpted pieces like incense burners, figurines, etc.

I did my first application, got a nice patina pattern across a curved piece, gonna touch up with a combination of a bottle of brasso I picked up and a box of Q-tips to randomly deoxidize with spots and striping in combination of using the mustard method in the next application..

Fun :cool: / SB!!