Proportions on various wootz etching solutions

Jeff Pringle · 20th February 2007, 03:57 PM

The more dilute the etchant is, the smoother the 'bite' and the longer it takes to do the etch. So start out with a low perecentage and if it's taking too long, make the solution stronger. If it's too strong you'll get a rough finish that looks bad.
For Ferric, I use the liquid PCB etchant and dilute it three or four parts water to one FeCl. If you are using powdered, I'd say make it about the color of 18 year old Macallan's and adjust up or down.
Degrease, in for thirty seconds, rinse, check, repeat; adjust time in the solution or solution strength. Wipe off the accumulated etching debris or they will interfere with the etch.
The copper sulfate should give you some cool effects when the copper plates out of solution!

ariel · 20th February 2007, 10:22 PM

18 yo Macallan as a color yardstick...
Single malt, of course.
But... is it single cask?

Bill M · 21st February 2007, 01:34 AM

Brian,

Whatever dilution, use DISTILLED water! I have found that tap water can make the color come out brownish.

Also be sure to have some amonia or baking soda to stop the etch when you get it like you want it.

DaveS · 27th February 2007, 03:15 AM

Brian: Instead of using ferric chloride, you might want to try phosphoric acid. It is sold by Orchard Supply Hardware under the name "metal etch" I have used it for many years to etch layer welded blades, especially moro swords. I think it gives a much better look to the steel, a silver and black look. I used ferric on wootz until just recently. I tried phosphoric on a wootz piece and the results were outstanding. Instead of diluting it ,use it right out of the bottle as i have found it really dosen't need to be diluted. It also helps if the blade is warmed with a propane torch. Just warm enough so you can't hold your hand on it. It makes the high carbon areas stand out better. Ferric chloride always seems to give a gray-green etch which i dont think looks as good as a phosphoric etch. I also have never had a problem with using straight tap water. Possibly my area of the country (Central Calif) might have different or less dissolved minerals than where Bill lives (Atlanta). That might make a big difference in the kook of the final etch.....Dave

Pukka Bundook · 27th February 2007, 01:49 PM

Dave,
thanks for the tip re. phosphoric acid.
I see you use the "metal etch" neet. Would you mind telling me how you apply it, and, How long do you leave it on the metal?
Thank you again Dave,

All the best,
Richard.

DaveS · 27th February 2007, 10:09 PM

Richard: I use a paint brush. I hold it by the handle and just apply it to both sides making sure that the blade is covered evenly. If you have warmed the blade with a propane torch sometimes the acid will smoke a little. this won't hurt anything. As to how long you need to wait for the etch to be complete, this will vary with the type of metal, number of layers, how much carbon has been put in the blade during forging. The more pieces you do, the more you will be able to know when to rinse and neutralize. Generally, iv'e found that the longer the acid is on, the darker the etch, so it will be a matter of personal preference how dark you might want the etch. I seem to get better control of the shades of light and dark if i etch out in the bright sunlight where i can better see what the final contrast will be. If the etch seems to be a little dark then you can take a steel wool pad and rubbing lightly take away some of the etch. This has worked for me........sometimes. Otherwise you will need to take some 1500 wet and dry and buff off the etch. Another thing i have found is that the higher the polish on the blade , the better it looks like it has put under a pane of glass. This is all a matter of personal preference. Some don't like an etch that looks like this, some do. Regardles of how you do it, the most important things to do are a thorough degreasing before etch, and a quick oiling after etch to prevent rust. If you have any problems, let me know. Hope this helps.............Dave

DaveS · 27th February 2007, 10:21 PM

Richard: Forgot to add that it important to keep applying the acid so that both sides of the blade are kept wet. Sometimes it comes out after less than a minute, sometimes it takes ten or even fifteen minutes but usually after five minutes if nothing happens, then nothing is going to happen. Iv'e had nothing much happen even if i know the blade is laminated. You will find that it can be very frusrating at times, but that it can be very rewarding when a beautiful pattern suddenly jumps out at you. It makes all the work you put in polishing a sword worth it...............Dave.

20th February 2007, 03:57 PM	#1
Jeff Pringle Member Join Date: Nov 2005 Posts: 189	The more dilute the etchant is, the smoother the 'bite' and the longer it takes to do the etch. So start out with a low perecentage and if it's taking too long, make the solution stronger. If it's too strong you'll get a rough finish that looks bad. For Ferric, I use the liquid PCB etchant and dilute it three or four parts water to one FeCl. If you are using powdered, I'd say make it about the color of 18 year old Macallan's and adjust up or down. Degrease, in for thirty seconds, rinse, check, repeat; adjust time in the solution or solution strength. Wipe off the accumulated etching debris or they will interfere with the etch. The copper sulfate should give you some cool effects when the copper plates out of solution!

20th February 2007, 10:22 PM	#2
ariel Member Join Date: Dec 2004 Location: Ann Arbor, MI Posts: 5,503	18 yo Macallan as a color yardstick... Single malt, of course. But... is it single cask?

21st February 2007, 01:34 AM	#3
Bill M Member Join Date: Mar 2005 Location: USA Georgia Posts: 1,599	Brian, Whatever dilution, use DISTILLED water! I have found that tap water can make the color come out brownish. Also be sure to have some amonia or baking soda to stop the etch when you get it like you want it.

27th February 2007, 03:15 AM	#4
DaveS Member Join Date: Feb 2006 Posts: 327	Brian: Instead of using ferric chloride, you might want to try phosphoric acid. It is sold by Orchard Supply Hardware under the name "metal etch" I have used it for many years to etch layer welded blades, especially moro swords. I think it gives a much better look to the steel, a silver and black look. I used ferric on wootz until just recently. I tried phosphoric on a wootz piece and the results were outstanding. Instead of diluting it ,use it right out of the bottle as i have found it really dosen't need to be diluted. It also helps if the blade is warmed with a propane torch. Just warm enough so you can't hold your hand on it. It makes the high carbon areas stand out better. Ferric chloride always seems to give a gray-green etch which i dont think looks as good as a phosphoric etch. I also have never had a problem with using straight tap water. Possibly my area of the country (Central Calif) might have different or less dissolved minerals than where Bill lives (Atlanta). That might make a big difference in the kook of the final etch.....Dave

27th February 2007, 01:49 PM	#5
Pukka Bundook Member Join Date: Jan 2007 Posts: 803	Dave, thanks for the tip re. phosphoric acid. I see you use the "metal etch" neet. Would you mind telling me how you apply it, and, How long do you leave it on the metal? Thank you again Dave, All the best, Richard.

27th February 2007, 10:09 PM	#6
DaveS Member Join Date: Feb 2006 Posts: 327	Richard: I use a paint brush. I hold it by the handle and just apply it to both sides making sure that the blade is covered evenly. If you have warmed the blade with a propane torch sometimes the acid will smoke a little. this won't hurt anything. As to how long you need to wait for the etch to be complete, this will vary with the type of metal, number of layers, how much carbon has been put in the blade during forging. The more pieces you do, the more you will be able to know when to rinse and neutralize. Generally, iv'e found that the longer the acid is on, the darker the etch, so it will be a matter of personal preference how dark you might want the etch. I seem to get better control of the shades of light and dark if i etch out in the bright sunlight where i can better see what the final contrast will be. If the etch seems to be a little dark then you can take a steel wool pad and rubbing lightly take away some of the etch. This has worked for me........sometimes. Otherwise you will need to take some 1500 wet and dry and buff off the etch. Another thing i have found is that the higher the polish on the blade , the better it looks like it has put under a pane of glass. This is all a matter of personal preference. Some don't like an etch that looks like this, some do. Regardles of how you do it, the most important things to do are a thorough degreasing before etch, and a quick oiling after etch to prevent rust. If you have any problems, let me know. Hope this helps.............Dave

27th February 2007, 10:21 PM	#7
DaveS Member Join Date: Feb 2006 Posts: 327	Richard: Forgot to add that it important to keep applying the acid so that both sides of the blade are kept wet. Sometimes it comes out after less than a minute, sometimes it takes ten or even fifteen minutes but usually after five minutes if nothing happens, then nothing is going to happen. Iv'e had nothing much happen even if i know the blade is laminated. You will find that it can be very frusrating at times, but that it can be very rewarding when a beautiful pattern suddenly jumps out at you. It makes all the work you put in polishing a sword worth it...............Dave.