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festally
03-04-2011, 12:14 PM
While fixing some ootb grinding issues, I ended up mucking up and needing to restore the damascus pattern on a Tanaka blue petty. I followed Davesí etching tutorial using a mixture of vinegar and muriatic acid (couldnít find the radio shack stuff) and after several tries, got the damascus pattern looking ok. I may do it again cause it came out a bit bolder than I had hoped for.

Q1. Is there a way to preserve the look of the damascus, while inhibitting the carbon natural desire to rust and reactive to acidic foods at the same time?

Darkhoek
03-04-2011, 05:24 PM
The etching will leave a lot of microscopic voids in the steel that goes dark. These voids will collect moisture. Oiling the blade with some food oil will seal off those dents and will make the blade less prone to rust and discoloration.

DarkHOek

festally
03-04-2011, 06:26 PM
Yup, the rust is coming from the black lines. I put a light coat of veggie oil on it, but will I have oil it on a regular/ ongoing basis?

I didnít experience any rust issues or need to oil - prior to etching. i just wiped the blade dry.

Darkhoek
03-04-2011, 06:45 PM
It's the micro pitting caused by the etching that hosts moisture and shait and causes the rusting. Washing the blade in hot water and drying it afterwords will get the blade dryer as the hot blade will vaporize the water in the pits faster. After a while of careful use, the blade will build a patina, but that will dull the contrast in the damascus as well I am afraid. Solution is stainless damascus...

DarkHoek

SpikeC
03-07-2011, 05:13 PM
Muriatic acid will leave chlorine residue inYou need to properly neutralize the metal or it will continue to be problematical.

PierreRodrigue
03-07-2011, 07:48 PM
I have been told windex will neutralize FC, I know a couple other makers that will boil a freshly etched blade is a heavy concentration of baking sode and water. It seems to "set" the oxide formed, making it less likely to rub off. it seems to work, I do this as well. Others have mentioned useing a food grade dry silicone spray, I'm not sure of this one... just a wee bit leary of surface treatments on kinves.

SpikeC
03-07-2011, 08:10 PM
I think that the baking soda is the best way with this.

Delbert Ealy
03-07-2011, 09:59 PM
Since I have been making damascus for over 24 years, I have tried almost everything imaginable. The reason a lot of people use windex for a neutralizer is because it contains ammonia. I have used baking soda as well. For re-etching and neutralizing the baking soda and hot water can be problematic because of the handle, if you are doing a full re-etch. I use ammonia and water as a neutralizer. For full drying afterwards use a hair dryer. As for the final finish, oils wash away too easily, I have found that waxes(food-safe of course) provide a much better finish and they fill in all that rough micro surface.

Chef Niloc
03-07-2011, 11:25 PM
Since I have been making damascus for over 24 years, I have tried almost everything imaginable. The reason a lot of people use windex for a neutralizer is because it contains ammonia. I have used baking soda as well. For re-etching and neutralizing the baking soda and hot water can be problematic because of the handle, if you are doing a full re-etch. I use ammonia and water as a neutralizer. For full drying afterwards use a hair dryer. As for the final finish, oils wash away too easily, I have found that waxes(food-safe of course) provide a much better finish and they fill in all that rough micro surface.

Yet another use for Dave's bored butter!

festally
03-08-2011, 12:45 AM
I did neutralize the Muriatic acid with some windex, and also gave it a long soak in a hot water/ baking soda solution – just in case there was some leftovers. I use it to clean the patio and know the stuff is pretty nasty. The fumes alone ate some paint cans.

A damascus carbon blade reminds me of a black colored car – looks great when freshly detailed, but the upkeep is pita. Eventually I’ll just let it go and build a patina or baking soda polish like regular carbons.

In the mean time, I wouldn’t mind trying to re-etching again and was wondering…
A) Would presanding to a higher grit (>1000) created a smoother textured finish?
B) What would cause some lines to come out crisp while others are blurred?

Delbert Ealy
03-08-2011, 01:00 AM
I did neutralize the Muriatic acid with some windex, and also gave it a long soak in a hot water/ baking soda solution – just in case there was some leftovers. I use it to clean the patio and know the stuff is pretty nasty. The fumes alone ate some paint cans.

A damascus carbon blade reminds me of a black colored car – looks great when freshly detailed, but the upkeep is pita. Eventually I’ll just let it go and build a patina or baking soda polish like regular carbons.

In the mean time, I wouldn’t mind trying to re-etching again and was wondering…
A) Would presanding to a higher grit (>1000) created a smoother textured finish?
B) What would cause some lines to come out crisp while others are blurred?

Presanding to a higher grit is a waste of time, it doesn't make any difference after 5 min or so in the etch. The differences in the lines are the different steel alloys, some etch out faster and some slower. You might try lighly sanding the surface after the etch with very high grit sandpaper, I use 2000 grit.
I use one of my own knives in my kitchen, a damascus one, using the methods I listed above, since september of last year. I have only wipe the blade with a soapy sponge and rinsed the blade in running water, then a quick wipe with a towel. I do this after I finish cutting up the food for the evening meal. In all that time there have been no blemishes and the blade looks like it did when I first finished the knife.

antonio_luiz
03-08-2011, 05:34 AM
You do realise that Muriatic Acid is actually Hydrochloric Acid (HCl). You can also etch with Ferric Chloride - the same stuff as was used for etching printed circuit boards - this is not as aggressive as HCl

StephanFowler
03-08-2011, 09:57 AM
I have been told windex will neutralize FC, I know a couple other makers that will boil a freshly etched blade is a heavy concentration of baking sode and water. It seems to "set" the oxide formed, making it less likely to rub off. it seems to work, I do this as well. Others have mentioned useing a food grade dry silicone spray, I'm not sure of this one... just a wee bit leary of surface treatments on kinves.

I use Tri-Sodium-Phosphate (TSP) it's a cleaning agent you can get in most home improvement store paint departments.
It's cured a LOT of my rusting issues over the years.

StephanFowler
03-08-2011, 10:02 AM
B) What would cause some lines to come out crisp while others are blurred?


I can't speak to what exactly is going on with your specific knife but one common cause of that is differential hardening.

Hardened damascus etches differently than un-hardened.
typically the spine will be softer than the edge due to varying thickness when the blade was quenched. which if dramatic enough (5-6 points RHC) can cause a visible difference in the etch.

Also if there were any oils (like from your fingers) or other residue on the blade when you etched you would have some funky results from etching.

I always clean the blade thoroughly with 409 and give a final wipe with denatured alcohol and a lint free cloth when I am etching something.

festally
03-08-2011, 10:24 PM
Thanks for the advice and sharing your metheods. It sounds like I dropped the ball in several areas – most of all my sort of dry, probably left enough moisture to rust and the rust cause some lines to blurr. I’ll try to find some FC and TSP and do a better job of a) cleaning the blade well prior to etching, b) sanding it at a higher grit between the dips, and c) making sure it’s really dry with a hair dryer.

Darkhoek
03-09-2011, 04:18 AM
Thanks for the advice and sharing your metheods. It sounds like I dropped the ball in several areas – most of all my sort of dry, probably left enough moisture to rust and the rust cause some lines to blurr. I’ll try to find some FC and TSP and do a better job of a) cleaning the blade well prior to etching, b) sanding it at a higher grit between the dips, and c) making sure it’s really dry with a hair dryer.

Using hot tap water when washing off your knife and drying it off thorouhly and immediately will let you skip the hair dryer as the heat in the blade wil evaporate the water residue.

DarkHOeK

EdipisReks
03-09-2011, 09:02 PM
While fixing some ootb grinding issues, I ended up mucking up and needing to restore the damascus pattern on a Tanaka blue petty. I followed Davesí etching tutorial using a mixture of vinegar and muriatic acid (couldnít find the radio shack stuff) and after several tries, got the damascus pattern looking ok. I may do it again cause it came out a bit bolder than I had hoped for.

Q1. Is there a way to preserve the look of the damascus, while inhibitting the carbon natural desire to rust and reactive to acidic foods at the same time?

i've etched a few knives, and you definitely want to coat it with some mineral oil or similar.