1. Click here to enter the drawing for your chance to win an Ontario Knives Spec Plus SP8 Machete Survival Knife & Ka-Bar Dozier Folding Hunter, , Bladeforums.com swag or memberships!

    Be sure to read the rules before entering, then help us decide next week's giveaway by hitting the poll in that thread! Entries close at midnight, Saturday Sept 7!

    Once the entries close, we'll live stream the drawing on Sunday, Sept 8 at 5PM Eastern. Tune in to our YouTube channel TheRealBladeForums for a chance to win bonus prizes!

    Questions? Comments? Post in the discussion thread here

lemon juice etching

Discussion in 'Himalayan Imports' started by Pan Tau, Mar 7, 2003.

  1. Pan Tau

    Pan Tau

    Sep 3, 2002
    just tried do do some lemon-juice-etching on my chiruwa - just to try it out. Got a nice foliage pattern (wrapped the blade with lemon-juice soaked paperhandkerchiefs and left it for one night), kind of natural camo with different greys and shady brown tones. Is the brown stuff rust (there is no coating or something)? And does the etching provide some kind of rust-protection? :confused:
    A question for those who use ferric chloride for etching, is it ferric(II)chloride or ferric(III)chloride?
    I know there are some specialists out there (Keith?)....

    Thanks in advance,
  2. spence


    Jan 11, 2002
    Hopefully, Ferrous or Federico will post a reply.

    In the meantime...

    I've etched a couple of blades using lemon + lime juice and varying dilutions of vinegar.

    I've never gotten a uniform etch on an HI khuk, even when soaking the blade completetly in the solution. So, your "foliate" results aren't a surprise.

    I don't think that the brown areas are of concern (assuming they feel smooth to the touch, not rough or pitted). As long as you have neutralized the acid, I wouldn't be too worried. Gun barrels used to be etched for rust protection. The process was called "browning" before it was called "bluing" (i.e. the steel developed a brown patina).

    My HI khuks have had a few brownish spots post-etch, though I mostly got greys and blues.

  3. Pax-V


    Apr 14, 2002
    I've used the etch Radio Shack sells. Its for etching circuit boards. Works great. Dilute it down with water.
  4. Tohatchi NM

    Tohatchi NM

    Mar 26, 2002
    Ferric chloride is Iron (III) Chloride, FeCl3

    Ferrous chloride is Iron(II) Chloride, FeCl2
  5. Bill Martino

    Bill Martino

    Mar 5, 1999
    I don't etch anything on purpose so can't help. But I sometimes do by accident.
  6. Pan Tau

    Pan Tau

    Sep 3, 2002
    Thanks Spence,Tohatchi and Pax V,
    due to my English I did not know the difference, in German both is "Eisenchlorid".
    I have not neutralized the lemon juice, just washed it away with a lot of water and rubbed the blade dry with cloth - big mistake? :confused:
  7. Tohatchi NM

    Tohatchi NM

    Mar 26, 2002
    In english, we would say "Iron Chloride" Ferric and Ferrous denote the specific oxidation state of iron (iron II or III). The Germans were on the cutting edge of chemistry as it was emerging (and still are, though the default language seems to have become English) so I suspect that german has some speciallized language that tells the difference. Then again, with German efficiency, they may just use II and III to tell the difference.

    As long as you rinsed very well, I doubt you'll have problems. You might want to wash with soap and hot water. A solution of baking soda and water would be good for neutralizing, if you're really worried. Remember to oil or wax the blade to prevent rust.
  8. Pan Tau

    Pan Tau

    Sep 3, 2002
    Thanks Tohatchi,
    we do make the differenc and speak of "Eisenzweichlorid" (Iron(II)chloride)or "Eisendreichlorid"(Iron(III)chloride). I will wash the blade with soap and hot water again. What problem would occur if I did not neutralize enough?

  9. spence


    Jan 11, 2002

    If you had active acid on the blade, it would continue to oxidize, and you might get rust or pits.

    I used baking soda and water to neutralize, although soap and water should work, too.

    Then, per Tohatchi, dry and oil.

    One of my old gunsmithing books has a recipe for browning solution. Basically it's iron nails disolved in a mild acid. Someday, I'm going to give that a try.


    PS. Your patina will wear off with use.
  10. Pan Tau

    Pan Tau

    Sep 3, 2002
    Thanks for your help,
    it comes out a bit like marble I think, funny effect, will have to get used to it I guess - or remove the patina. I scanned the blade (the blade, not a photo of it - quality is not so good) and tried to show you the pic within the post - but it does not work with pics from these microsoft galleries, don't know why. Here's the link

    etched chiruwa

    You should be able to get there.


    P.S. Spence, I hope MY patina is not that obvious as that on the blade... ;) (feeling to young for such a thing...)

    edited for P.S.
  11. ddean


    Mar 26, 2002
    Clean the blade carefully & thoroughly with soap and non-abrasive scrubby or cloth. This gets rid of any oil or other coating (fingerprints and other) that might 'resist' the etchant. Don't touch the blade with fingers aftwer its cleaned.

    Add a few drops of the soap (I use dish soap) to the dilute etch solution and mix.

    Rub the citus / vinegar etchant onto the blade with a pad or non-abrasive scrubby using continous, slow --Careful-- motion. I keep the edge downward so the etchant can't pool under the blade in droplets. You could probably just dip it in and out of the solution slowly.

    Just takes 5,10,15 minutes.
    Warm solution &/or blade goes faster then cool.

    With a cleaned blade and soap in the etchant, you would probably get an interesting effect as the etchant gets depleted slightly in the more active etching areas if the solution is completely still (or just an even etch if I'm wrong.)
  12. Tohatchi NM

    Tohatchi NM

    Mar 26, 2002
    Awesome tip on the soap! Reduce surface tension = no beading = more even etch!
  13. Federico


    Sep 5, 2000
    Ow...you dont need to leave the etchant on for so long. Many people are surprised at how agressive lemon juice can be as an etchant. The topogrophical textures of Indo keris is made just by lemon juice. What I would suggest right now is to wash the blade with soap and water, and then oil it a bit with a penetrating oil like WD-40. Let it sit for a bit and then scrub lightly with 0000 steel wool. This will help get rid of any active rust, and will help even out the finish.

    Here are tips for at least what has helped me in etching.

    1. Always make sure the blade is properly degreased. Even the slightest bits of grease from even just fingerprint can screw things up. I normally wash the blade with hot water and dish soap a few times, after drying I then wipe it down a few times with rubbing alcohol and paper towels. Acetone works well also instead of rubbing alcohol.

    2. Warm blade and etchant helps the etchant bite better. If its a hot summer day, leaving you etchant and blade out in the sun for a few hours works. However since its winter, heres what I do. I take the bottle of etchant (ferric chloride or lemon juice) and sit it in front of my heat vent for a while (an hour or two) to help it warm up. After wiping the blade down with alcohol (last stage of degreasing. I then light up the propane torch and give it a few quick passes (I stress quick) over the blade to warm it up a bit. Again youre not looking for red hot, just looking to warm up the blade a bit.

    3. Brushing the etchant works great. When Im ready to etch I usually brush the etchant on with a tooth brush. The agitation helps the etchant spread evenly, and keeps it from settling. I dont soak the blade, instead I just stand it up or hold it and continually brush on the etchant.

    4. Multiple short etches instead of singular long ones. I prefer doing a five 5 minute etch cycles over one long one. Meaning etch the blade, wash (neutralize acids), remove oxides (oil and steel wool), degrease, and repeat. I prefer this method, because if you make a mistake, or the etchant doesnt settle right the first time round, if you let it sit too long it burns its way into the steel (hope that makes sense) making more un-even patterns more common. Whereas with multiple short etches, un-even patterns dont get burned into the steel, you can keep an eye on progress, etc...

    5. Keep an eye on it. If you have done thing right, the etch should be darn near instant. Dont over burn the blade in one pass. Keep an eye on it, and stop when things start to look like theyre going nowhere.

    6. While supposedly the stable oxides created by etching should help prevent rust, Ive noticed blades that are recently etched are more succeptable to rusting early on. Meaning, for the first couple months after etching the blade is more sensitive to rusting. One explanation Ive heard is that the etchant opens up the pores of the steel. Well for whatever reason, keep an eye on your blade for the first couple months, and keep it well oiled. After that, it does stay pretty neutral.

    7. ooh before I forget, texture in the steel means texture in the etch. So make sure your blade is perfectly smooth before etching. The magic polish is somewhat misleading, as its super shiny. Just because you can see yourself in you blade doesnt mean its perfectly smooth. So you may want to sand it first to even out the finish. However sometimes the funky patterns of the texture looks neat, kinda like fake damascus.

    Well those are my tips for etching, hope they help.
  14. sweet


    Nov 11, 1999
    I have yet to do this with one of my H.I maybe I might have to try it out down the road...I used a method that the late Bob Engnath taught me when I was buying his Yakiba blades years ago...these blade are from Kris Cutlery and are made from 5160 with a differential temper that I brought out using 5% white vinegar

    edit to add the link
  15. Ferrous Wheel

    Ferrous Wheel

    May 16, 2002
    I have those same blades, sweet! I also like the vinegar etch.

    Pan tau-- Cool pattern on the blade. Fed posted all the stuff I would, excellent Fed! I use a 1:1 ratio of distilled water to FeCl. Warm works best. Cuts fast, so light ethcing is done after two minutes. Deep pitting etching can be done by leaving it in solution for 30-45 minutes. Longer could be bad. Sa to the II or III thing, I don't think that matters.

  16. Pan Tau

    Pan Tau

    Sep 3, 2002
    Thank you,
    learned a lot - maybe I should have asked before I tried it :rolleyes: . I think as I look at it I get to like the pattern...

  17. spence


    Jan 11, 2002
    Thanks much for the additional info, Fed, ddean, sweet and Ferrous.

    Sweet, those pics are gorgeous.

    I've been able to get an even etch on other, production carbon blades (primarily kitchen knives). My guess is that it is due to differences in the finish, as Fed says. I'm not disappointed in the results on my HI blades by any stretch. Like Andreas, I think the pattern is interesting.

  18. Federico


    Sep 5, 2000
    Monosteel blades that are completely through hardened (hmm I think thats the right term) are about the only things that will give you a straight even etch off the get go. Besides uneven finish before etching (such as ripples, scratches, etc...), carbon content (as in pattern welded blades), and differences in hardness (as found in differential hardened blades) will also give un-even coloing.

    Etching is a great way to see how blades are made. You can see if its pattern welded, how it was hardened, and sometimes (when you get funky colors like green or no reaction) you can see alloy content. Anyways, if your blade isnt monosteel through hardened (I have the sneeking feeling Im using the wrong term here but I mean a blade where the hardness is completely even all out) trying to force a perfectly even etch can be a pain.
  19. shappa


    Oct 15, 1998
    Pan Tau... cool etch...looks like stone!
  20. Federico


    Sep 5, 2000
    I forgot to add. Iffen your etch goes horribly horribly wrong, you can always sand through it and start over again. Of course the deeper the etch the more sanding youll need to do.

Share This Page