unusual small little moro kris for id please

Battara · 7th August 2019, 11:49 PM

For me ferric chloride is the closest to the vinegar and fruit etching in color. Green? - weird......not happened to me, only browns and yellows.

Also I totally agree with the rubbing down with baking soda after the etch - this stops the continued etch and prevents eventual corrosion post etch.

kai · 8th August 2019, 06:33 AM

Hello Jose,

Quote:

I totally agree with the rubbing down with baking soda after the etch - this stops the continued etch and prevents eventual corrosion post etch.

Sure, with most acids a neutralization step is crucial. However, the main problem with ferric chloride is that it promotes corrosion even after full neutralization: any remaining chloride ions will act as catalyst for rusting. Forever! With many antique blades removing all chloride by rinsing/soaking is a real challenge if at all feasible!

BTW, the beauty of acetic acid (vinegar) is that any traces will evaporate upon gently heating the blade.

Regards,
Kai

Battara · 8th August 2019, 06:56 AM

Hi Kai. I have not had the problem. I guess by washing it off first, then rubber it with baking soda, then drying the blade off by rubbing, and then oil.

kai · 8th August 2019, 06:55 AM

Hello Jose,

Quote:

For me ferric chloride is the closest to the vinegar and fruit etching in color. Green? - weird......not happened to me, only browns and yellows.

Those browns and yellows are active rust - I’d be weary about any of these warmer colors!

I suspect that varying (technical) qualities of ferric chloride as well as different usages and possibly recycled etchant are responsible for variable results.

Greenish colors may result from copper dissolved in the etchant by contact with brass, etc.

Regards,
Kai

kai · 8th August 2019, 05:27 PM

Hello Dave,

I reckon such a stock lasts for ages - could you possibly check the concentration of a fresh can if you get a chance at a store or so, please? I’m sure it’s not concentrated phosphoric acid - probably 10% or less.

The acid in coke is much more diluted - I’m sure it will work but requiring much longer exposure and the heaps of sugar may make this a quite sticky affair!

Regards,
Kai

DaveS · 8th August 2019, 10:34 PM

Yeah i was thinking the same thing......That it would be so diluted that it would take some time to work. And yes, i imagine it would be a sugary mess if it worked at all. I just went out into the shop and looked on the bottle to see what % it was. Guess what!!. Looked all over, every where and it says nothing about what strength it is. I thought that was required. Looked three times and nothing. When i get the chance i'll get a different brand and will look again.

Rick · 9th August 2019, 04:30 AM

There's always instant coffee paste to try.

mross · 9th August 2019, 02:51 PM

If any of this is tried please post results what ever they may be. I would suggest using a salon type hair dryer or a heatgun on low-med rather than a torch to heat it up.

chiefheadknocker · 10th August 2019, 08:13 PM

Hi all , i bought some ferric chloride to help etch the blade but after hearing about the concerns of it keep corroding the blade has made me think twice, and so ive held off , ive cleaned the blade a little more and heated it then used vinegar again , after leaving it for some time the blade turns a brownish colour ,once washed off it leaves a kind of patchy effect most the darkening effect on the out side of the blade leaving the centre pretty much untouched , ive repeated this process a couple of times but no signs of any twist core ,
i think its maybe to leave it now ?
Thanks for all your replies

7th August 2019, 11:49 PM	#1
Battara EAAF Staff Join Date: Dec 2004 Location: Louisville, KY Posts: 7,272	For me ferric chloride is the closest to the vinegar and fruit etching in color. Green? - weird......not happened to me, only browns and yellows. Also I totally agree with the rubbing down with baking soda after the etch - this stops the continued etch and prevents eventual corrosion post etch.

8th August 2019, 06:56 AM	#3
Battara EAAF Staff Join Date: Dec 2004 Location: Louisville, KY Posts: 7,272	Hi Kai. I have not had the problem. I guess by washing it off first, then rubber it with baking soda, then drying the blade off by rubbing, and then oil.

8th August 2019, 05:27 PM	#5
kai Member Join Date: Apr 2005 Posts: 3,255	Hello Dave, I reckon such a stock lasts for ages - could you possibly check the concentration of a fresh can if you get a chance at a store or so, please? I’m sure it’s not concentrated phosphoric acid - probably 10% or less. The acid in coke is much more diluted - I’m sure it will work but requiring much longer exposure and the heaps of sugar may make this a quite sticky affair! Regards, Kai

8th August 2019, 10:34 PM	#6
DaveS Member Join Date: Feb 2006 Posts: 327	Yeah i was thinking the same thing......That it would be so diluted that it would take some time to work. And yes, i imagine it would be a sugary mess if it worked at all. I just went out into the shop and looked on the bottle to see what % it was. Guess what!!. Looked all over, every where and it says nothing about what strength it is. I thought that was required. Looked three times and nothing. When i get the chance i'll get a different brand and will look again.

9th August 2019, 04:30 AM	#7
Rick Vikingsword Staff Join Date: Nov 2004 Posts: 6,336	There's always instant coffee paste to try.

9th August 2019, 02:51 PM	#8
mross Member Join Date: Jan 2005 Posts: 478	If any of this is tried please post results what ever they may be. I would suggest using a salon type hair dryer or a heatgun on low-med rather than a torch to heat it up.

10th August 2019, 08:13 PM	#9
chiefheadknocker Member Join Date: Dec 2014 Posts: 143	Hi all , i bought some ferric chloride to help etch the blade but after hearing about the concerns of it keep corroding the blade has made me think twice, and so ive held off , ive cleaned the blade a little more and heated it then used vinegar again , after leaving it for some time the blade turns a brownish colour ,once washed off it leaves a kind of patchy effect most the darkening effect on the out side of the blade leaving the centre pretty much untouched , ive repeated this process a couple of times but no signs of any twist core , i think its maybe to leave it now ? Thanks for all your replies