Blade etching

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malcolm47

Joined
Oct 11, 2005
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Could anyone please post how to etch a blade using lemon juice. I also need to know how to nutralize the blade afterwards. I know it's been posted before but I'm not sure what post it was in :rolleyes: . Thanks a lot.................Malcolm
 
You can search the forum for this info, malcom. ;)

If I recall correctly, the process is as follows:

1) clean the blade
2) clean the blade again
3) clean the blade with a degreaser - acetone, turpentine, ammonia, etc.
4) rub the blade with lemons (or a lemon juice/cornstarch paste) until it achieves a colour slightly darker than what you want as the final result.
5) wash the blade thoroughly with warm water
6) neutralize the acid with a gentle basic solution, such as 50/50 baking soda and water.
7) wash and gently buff dry
8) oil!
 
Kazeryu has it right. Please understand that there are as many methods to etch blades as there are people that do it. Do a search on etching and read what others have to say. This is what I've compiled over the years.


1. Use acetone or denatured alcohol to degrease the blade. Both are flammable, so use good ventilation and follow the safety instructions on the can.
2. Cut a lemon, lime or other acidic fruit, and rub on the blade. Rub one side, then the other. Repeat until the pattern develops to your liking.
3. Rinse the blade in cold water.
4. Neutralize the acid by rubbing the blade with a thick mixture of baking soda (sodium bicarbonate) and water, or with ammonia, or window cleaner containing ammonia.
5. Rinse the blade in cold water.
6. Dry the blade thoroughly, and oil it well with mineral oil, or whatever you currently use to prevent rust.

An alternative is to use ferric chloride. It works quicker and sometimes brings the pattern out better, but is potentially more dangerous to the blade.

1. Use acetone or denatured alcohol to degrease the blade. Both are flammable, so use good ventilation and follow the safety instructions on the can.
2. Mix one part Ferric Chloride, available in the US from Radio Shack as Printed circuit board etchant, with 3 or 4 parts distilled water.
3. Using rubber gloves saturate a rag or paper towel with the solution and rub it onto the blade. Put it on with a fully saturated rag, and wipe it on evenly. Do one side then the other, doing your best to cover the full side of the blade in one pass. Don’t let the solution run down into the grip. I use a plastic trough that is used to wet wallpaper that I bought at the local home improvements store to catch the drips.
4. When satisfied with the pattern, rinse with cold water.
5. Rub the blade with a rag or paper towel saturated with vinegar. I’ve read that this helps to stop the ferric chloride reaction.
6. Rinse with cold water.
7 Neutralize the acid by rubbing the blade with a thick mixture of baking soda (sodium bicarbonate) and water, or with ammonia, or window cleaner containing ammonia.
8. Rinse with cold water.
9 Dry the blade thoroughly, and oil it well with mineral oil, or whatever you currently use to prevent rust.
 
there's also the hot vinegar (with a drop of soap in it) method.

Whatever the etchant, the method is usually the same:

1 - clean
2 - etch
3 - polish/clean



Steve, I hope I didn't pass on bad information....but vinegar is indeed an etchant and not a neutralizer. It's also a good cleaner, so that may be why some folks use it.

I leave blades in vinegar over night to etch the scale off of them and give them and "aged" look.


The best neutralizer (and easiest to get ahold of) that I've found is Windex.


You can also use chlorox bleach - to etch. ;)
 
Has anybody thought of perhaps coating the blade in wax or some other covering, scraping some kind of design into it, then etching the blade so that the design is etched onto the blade? The rambling thoughts of my mind hit on that at some point and i was wondering if anyones tried it or thought of it.
 
Daniel Koster said:
Steve, I hope I didn't pass on bad information....but vinegar is indeed an etchant and not a neutralizer. It's also a good cleaner, so that may be why some folks use it.

I leave blades in vinegar over night to etch the scale off of them and give them and "aged" look.


The best neutralizer (and easiest to get ahold of) that I've found is Windex.
Click to expand...

Dan, You are quite correct. Vinegar is indeed an etchant. My understanding though is that it neutralizes Ferric Chloride. It then has to be neutralized by ammonia or windex. I certainly don't understand the chemistry. This is what Firkin posted in the bladesmith's forum once.

Steve


An explanation why Vinegar is used to neutralize FeCl, by Firkin of Bladeforums:
Interesting discussion. I'll butt in if I may.

Simple protic acid/base neutralization concepts won't work for this system of ferric chloride in water, in the presence of air (oxygen).

The system is actually very complicated. But think of oxidation (as in burning), which is what etching and rusting is.

As I understand it, an approximate summary is that, ferric chloride (also known as iron(III) chloride) can covert to iron oxides and iron hydroxides (rust) in the presence of oxygen and water. This releases hydrochloric acid, which attacks the iron in the blade, making hydrogen, and ferric chloride (and iron(II) chloride also known as ferrous chloride) again.
Repeat the conversion of the two types of iron chloride to hydrochloric acid using oxygen from air dissolved in the solution and continue. .

The actual concentration of acid may never be large enough in the bulk solution to be measurable, or considered acidic. But it never gets used up, as the cycle continues to replenish it. But oxygen and the blade continue to be consumed to make iron oxides and iron hydroxides. As iron hydroxides build up, the bulk solution will become somewhat basic. But corrosion will still continue until it gets very basic.

Masochists may get some idea of what's involved by looking at the summary section of this article on corrosion which describes the role of iron chlorides:

http://nautarch.tamu.edu/class/anth605/File9.htm

What is needed is to remove all traces of ferric chloride and ferrous chloride because they let the chloride ions be used over and over again to attack the blade as hydrochloric acid. So the chloride ions are what make this system so effective at eating iron.

Excess ammonia solution (a base, but also a good ligand for iron ions) probably converts nearly all of the iron chlorides to less corosive ammonia complexes of some sort. And any free hydrochloric acid will be neutralized as ammonium chloride, a salt.

Excess vinegar (solution of acetic acid, but the acetate ion half is a good ligand for iron ions) probably converts nearly all the iron chlorides to less corrosive acetate complexes.

Simple mechanical rinsing effects at work too, of course.

Either vinegar or ammonia, likely effectively no more ferric chlorides. But any chloride salts of whatever type left have potential to start rust and generate some iron chlorides, so rinse well with water. Undoubtably things are more complicated than I describe.

My suggestion:

Use more than one treatment with fresh vinegar or ammonia (some tiny proportion of the iron chlorides won't convert--but a tiny proportion of a tiny proportion gets pretty close to zero). And final rinses with water.

Scrub surface if any thing could be trapped under any crud on the surface.

I don't think that baking soda (sodium bicarbonate) solution will convert iron chlorides to alternate, benign iron compounds as vinegar or ammonia will. Sodium bicarbonate makes a buffer solution, which means if enough is disolved, it self-regulates its pH until too much is used up reacting with acids. It holds pH 8.4, which is according to the alkaline inhibitive solutions section of the linked article not basic enough to inhibit corossion if chloride ions are present. Since it's a buffer, a solution cant be made any more basic than 8.4, no matter how much is dissolved. Household ammonia is a stronger base.

Lastly, I would not use vinegar and table salt, which one may come across in some discussions of "de-oxidants" for copper etching. That actually makes some hydrochloric acid. Which is why the mixture is so great for cleaning copper. Remember that those etching fragile copper PC boards want a totally clean, oxide free surface for later fabrication and they may do some things especially for that reason. Any very thin oxides that form on a blade by stopping an etch will be removed by polishing or soldering preparation.
 
great info, Steve - thanks. Will need to go back and read that again a few times...


skydog - David Boye does his etching that way. It's in his book.

The problem is getting the right wax and scribing it consistently. Plus build-up time and clean-up time.

But yes, it would allow you to etch a pattern or design into the blade.


A technique I picked up from Keith (Ferrous Wheel) is to use clear tape and cut the design out of the tape. Works for me.
 
Has anyone tried the concentrated lemon juice that they sell in the store for blade etching? It seems like it would do a better job than just a regular lemon, it's pretty potent. Thanks...........Malcolm
 
ALBPM said:
Can someone post some pictures of an etched Khuk??
Click to expand...

Done with Ferric Chloride
Steve

BGRSoverall.jpg


RoseOverall.jpg
 
thanks for the pics, ferguson, I was interested in seeing etched blades myself.

I was wondering what sort of difference you would see between etching a mirror-polish blade and a satin-finish blade... Could someone post side-by side pics of two etched knives - one originally satin, and one originally mirror?

I've been pondering etching my AK, and I'm sort of curious about the different 'final looks' which are possible.
 
Well the baby Ganga Ram was a villager and had a rough satin finish. But I sanded it before etching with some .....maybe 800 grit or 1000 grit sandpaper. The Cherokee Rose was mirror finished. But I've been told (don't know if it's true) that a buffed finish is hard to etch evenly. So I probably dulled it down a bit with 1500 or 2000 grit paper.

Guess I didn't really answer your question, did I?:o

Steve
 
Steve,

That Cherokee Rose is one dayum beautiful knife. WOW. I can feel the HIKV pulling me toward that one. I'm not going to hold it against you, but I'll be adding one of those to my list.:rolleyes: Thanks bud.

Andy
 
I've recommended it before and I'll recommend it again, hot vinegar. Of the readily available etches, regular-old-white-vinegar is the best; it is not too harsh and brings out all the elements of the hamon and steel, it is cheap, non toxic, and you can get it at the super market. It does stink and it takes more work, but the results are much better than ferric. Ferric is too harsh and over powers the finer subtleties of the steel, vinegar is mild and slow which high lights the steel's details.

When I suggest vinegar to people they generally blow me off and assume the extra work isn't worth the pay off.

Here's a shot of a vinegar etched hamon bowie I made a couple months ago.
attachment.php


I am developing a new etching technique that is far beyond hot vinegar, and I will post the details as my work continues...just and FYI :).

Matt
 
Longrifle, Can you use any white vinegar? I noticed that the vinegars in my food store say they are reduced with water to 5% acidity. Thanks for the helpful hint...........Malcolm
 
that's a sweet hamon line, Matt...!


I use distilled white vinegar. Seems to do the job and is fairly cheap.
 
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