Forced Patina?

[CJS Knives]

hey guys i want to do a forced patina using White Vinegar on a O-1 tool steel knife that i recently made. the knife has wood handles.

will this process effect the wood handles at all?

thanks guys,
Jeff

check out this amazing video of a forced patina.....

http://www.youtube.com/watch?v=yVfYJ-OALbQ&feature=channel_video_title

http://www.youtube.com/watch?v=yVfYJ-OALbQ&feature=channel_video_title

[Ray Rogers]

Generally speaking, I would expect wood handles to suffer if you boil them no matter what you boil them in. It isn't really necessary to boil the vinegar, just warm it to about 100 F in your microwave and then put the blade in it. The warm vinegar will probably stain the wood handle but total destruction is unlikely. Meanwhile, the steel will get black just as in the video.

BTW, Rc 61 or 62 on a thin blade like the guy in the video was talking about should be rather delicate for O1 ...

[CJS Knives]

thanks Ray, i wasnt planning on boiling the handles, but i know what you mean.

i also agree about the hardness of the blade in the video as well. thats a whole different topic i suppose! lol

[Crex]

Yeah, the vinegar with dissolved iron oxides from the blade will stain the wood even without boiling. The dissolved Fe will react with the tannins in the wood and turn dark. Higher the tannin level the darker the stain. Oaks and most maples will go coal black.
Boiling is not necessary just a warming plate (like for you coffee mug) or a hot light/lamp will suffice. One thing that helps with the etching is aggitation....some use acquarium pumps, etc. to keep the vinegar in motion.

It's a lot of fun to experiment with etching.
The first blade in the pic below was an experiment using some resist and a little imagination. Not exactly what I was shooting for, but turned out pretty neat. The blade is forged O1.
The second blade is OSB (old saw blade) and the etch was just enough to highlite the quench line. The guard, pommel and acorn are WI etched in the same solution. Sorry the picks don't do the WI justice, the ecth really brings out the layers just like PW steel.
The third blade is just some random pattern PW etched with the same solution (15n20 & 1084).
Note: I etch my blades before installing the handles.


Agree hole heartedly with Ray on the hardness factor for O1, that little blade would snap like glass in a leg bone joint without great care. Probably cuts like son of a gun, though.

[jcoon8283]

With the boiling point of water being 212*F and the low end of tempering for o1 being 350*F what are the chances this guy is ruining the temper on his knives? Seems a little close to me. I use strictly 1095 and etch all my knives with white vinegar but I never get the bath that hot ever, I test the temp regularly through the etch by dipping my finger in it and if it is even approaching uncomfortable to touch I remove the heat. After putting in the work to get the knife through ht and tempering why risk ruining it. By the way, he never mentions it in the video but you will need to soak your newly etched knives is some sort of acid neutralizer, I use good ol baking soda mixed into warm water.

[Ray Rogers]

If he's suspending the blade in boiling water the temper is likely unaffected. If the blade is laying on the bottom of the pan it might be getting hotter than the boiling water and the temper might be affected.

From the way the blade seems to cut I'd guess his temper was safe from the boiling but I agree with you, why take the chance? Anyway, he's tempering to 61 or even 62 he said so if the boiling is reducing the hardness it's probably a good thing.

[Crex]

Not much risk on the temper being affected, unless, as Ray mentioned about sitting in the bottom of the pot. The temp will have to clear 400*f to even get started on making any change to O1 other than eating it up with etchant (vinegar). I'd say it's just a way to get a more aggressive quick etch, but a waste of energy.

[CJS Knives]

i didnt think about neutralizing the vinegar after the soak. thats a good idea.

if you etch the blade before you put on the handle, how do you shape the handle (on a fixed blade) so that your dont sand off the etching on the spine of the knife?

[JCPollard]

Hi I know I am a newbie but I would temporarily fix the handle to the knife and shape like I was finishing. Then remove handle and do your etching or patina. I would think when you replaced the handles they would fit exactly as when assembled before unless you changed the profile of the knife itself. Looking forward to pics when its done.

[Ray Rogers]

Some people do it as JC suggested. Others put on the handle and shape it as needed and rub off the etch as they go. Afterwards, a cotton swap can be used to apply etchant to the exposed areas. Whichever way seems best to you ...

[Crex]

I usually do the latter with the cotton swab, just easier. Handle material has a way of mysteriously changing dimensions just a frog hair right before installation..........so it seems. I seal off the handle with a light tapeing and wax and then one pass with a swab of FeCl will usually do the trick. Neutralize with baking soda or amonia, clean up and wax it all. Takes a little practice but what doesn't?