Etching damasteel with Hydrochloric acid and coffee?

K

knifeaficionado

Joined
Jul 30, 2016
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Hello,

how should I go about for the best results with these components for etching damasteel?

How this process sounds:
final mirror polish first
Hydrochloric acid soak for around 10 minutes(cold)
coffee soak

Now I have a question also that should the blade be polished after the coffee soak also and how long should the blade be soaked in the coffee?

I guess it's enough just to make the coffee as strong as possible? I guess I'll be getting nescafe instant coffee for this.

THANKS!
 
How I go about it is similar...(ask 10 blacksmiths how to do something, you'll get 12 different answers...)
I hand sand to 400 grit, etch in acid for 15-30 minutes, neutralize, hand sand at 2000-5000g, then coffee for 4-8 hours.
I'm using strong (about 1-2 cups in ~ 1/2 gal H2O) generic cheap instant coffee, don't know what the comparison to nescafe is.

as always
peace and love
billyO
 
weo said:
How I go about it is similar...(ask 10 blacksmiths how to do something, you'll get 12 different answers...)
I hand sand to 400 grit, etch in acid for 15-30 minutes, neutralize, hand sand at 2000-5000g, then coffee for 4-8 hours.
I'm using strong (about 1-2 cups in ~ 1/2 gal H2O) generic cheap instant coffee, don't know what the comparison to nescafe is.

as always
peace and love
billyO
Click to expand...

Thanks.
I have few questions:
what's the difference between starting the etch after final polish vs after 400 grit? I thought that after etching any sanding will remove the pattern?

Does the coffee "corrode" the steel like the acid or does it just add color?

Does damasteel behave like any other damascus when etching?
 
While different folks get different results, based on my experience:

knifeaficionado, post: 18039042, member: 456792"]
I have few questions:
what's the difference between starting the etch after final polish vs after 400 grit?
High polish will be destroyed in the etch. Also, a 400 grit finish exposes more metal to the acid, and gets a better etch.
I thought that after etching any sanding will remove the pattern?
Some light sanding is needed to make the contrast between the deeper etched metal and the high spots. Use a fine paper (800-1000) with a hard rubber backing block.
Does the coffee "corrode" the steel like the acid or does it just add color?
Etch is just a term here, as the coffee only colors the metal. The blade needs to be completely done before the coffee etch. I haven't done Damasteel in coffee so I don't know how well it will darken. Carbon steel takes on a shiny jet black color. Coffee etch looks pretty, but is a surface effect only, and will rub off.
Does damasteel behave like any other damascus when etching?
Yes and no. It is a stainless steel, so the etch is slower, and less topographical. Other than that, it etches by the lower alloy steel in the mix eating away faster than the higher alloy steel. It doesn't etch as deeply, but I find that the pattern show well even when the steel is sanded to a near smooth surface after the etch. That is where I leave the finish on my damasteel kitchen knives. While some carbon damascus looks OK with a deeply ridged etch ( lots of topography), damasteel has much more pattern and looks best more subtle.
 
Do you have to use tge acid or can just etching with coffee work? Wjat about for a hamon?
Sorry man not trying to high jack your thread just in the same predicament (not using damasteel)
 
Thanks.
How does vinegar vs coffee compare to darken the patterns after the muriatic acid etch?

Is it normal practice to etch in muriatic acid a fully polished blade and not to sharpen after the etch? I am just wondering how much the acid dulls the blade.
 
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valnut,
Coffee doesn't etch. It only puts a black coating on the blade. It takes an acid like FC or hydrochloric (muriatic) acid to etch.
Hamons are an entirely diferent thing.

Knife aficianado,
Vinegar is a mild acid. It really won't etch damascus well, but will put a darker look on a carbon blade. Coffee is much blacker and shinier.
Vinegar doesn't do much at all to stainless steel.
You always have to sharpen last ... after the etch.
 
So now i have sanded up to 2000 grit the blade but still see fine sanding marks on the surface. Will the muriatic acid knock down those fine scratches and is it enough to use metal polish after the etch or is sand paper needed? I am just hoping to get a perfect mirror polish which seems rather difficult to achieve on hardened steel. Also I am looking for a shallow etch but enough contrast. That is why I am thinking about the coffee. Any experiences on how coffee colors damasteel?
thanks
 
Any thoughts? I'm planning to etch within two days and I'm wondering if I should get rid of the fine scratches first or if they'll disappear with the etch...
 
Damasteel would be the last thing to mirror polish. The difference between the steel types is what you are paying ( a lot) for. Making it all go away is a waste of time and money. At 2000 grit, you should not see scratches unless you didn't get out the earlier grit marks. You may be seeing "J"-hooks or drag lines from improper sanding technique. This is when the grit and swarf get balled up and make larger marks. Wet sanding above 400 grit is a way to reduce this. Also, try not to stroke back and forth at the higher grits.

Just go ahead and clean the blade well and etch. After the etch, give it a light sanding with 1000 grit and I think you will be happy.
 
Thanks Stacy.

I managed to get a good etch that has a good contrast and not much topography with 20 minute cold muriatic etch, it's so visible that I think I'll skip the coffee.

I think either I'm doing something wrong or have too high standards for a polish since even 2000 grit sandpaper leaves rather noticeable marks on the steel, even when it's supposedly at 57 HRC according to the test at the heat treat place. It also scratches rather easy with non hardened stainless steel. Is this normal for hardened steel to scratch so easily and is there a noticeable difference in scratch resistance in 57 HRC vs 60 HRC blade?
 
knifeaficionado said:
Thanks Stacy.
Click to expand...

Yep, I can always count on Stacy to clear up any confusion and posts with insufficient or misleading info.

knifeaficionado said:
I managed to get a good etch that has a good contrast and not much topography with 20 minute cold muriatic etch, it's so visible that I think I'll skip the coffee.
Click to expand...

Why not do a 4 hour dunk to see if it does anything to darken the blade/etch. The coffee doesn't really touch the 15N20 unless left in for a day or so.

knifeaficionado said:
I think either I'm doing something wrong or have too high standards for a polish since even 2000 grit sandpaper leaves rather noticeable marks on the steel, even when it's supposedly at 57 HRC according to the test at the heat treat place. It also scratches rather easy with non hardened stainless steel. Is this normal for hardened steel to scratch so easily and is there a noticeable difference in scratch resistance in 57 HRC vs 60 HRC blade?
Click to expand...

Hard to say without being there to see what you're talking about, but here's my guess as to what's going on. Your eyes may be too good, standards may be too high, who knows? When I started making knives, I noticed that when I started paying attention to the grits, even at 5000 I can still see the scratch lines if I then go the next step to 10000. But picking up a blade off the bench with a good 2000g finish, it looks to me like a pretty good mirror finish.

Also, if there is a truly mirror polish finish, any scratch, no matter how shallow is going to stick out like a sore thumb.

as always
peace and love
billyO
 
Hand rubbed finishes will "scratch" easily, what you're seeing is the raised "scratch pattern" of your linear hand-finish scratching most likely. If you're actually able to make a deep scratch with non-hardened stainless, then you likely have a significant layer of decarb, although if it's testing 57 with decarb, it means you're likely much harder below the surface.


Although, I'll also add, that you shouldn't be seeing anything other than fishhooks from a real 2000 grit finish, are you sure your paper isn't contaminated with courser grit? This can happen easily.

You can see fine grit scratches up to very high grit though, if you want a true mirror polish, you typically have to buff with compound or go to polishing papers.
 
I never asked, but how was the HT done?

As said, a mirror polish will show scratches by jsut rubbing it with your fingers.
 
Stacy E. Apelt - Bladesmith said:
I never asked, but how was the HT done?

As said, a mirror polish will show scratches by jsut rubbing it with your fingers.
Click to expand...

It was a vacuum heat treatment with the temperatures you gave me a while back.

Any thoughts on how would an etched damasteel look with surface grinding marks still left on and just buffed with some polishing paste? I guess any scratches would be less visible?

thanks
 
knifeaficionado said:
Any thoughts on how would an etched damasteel look with surface grinding marks still left on and just buffed with some polishing paste? I guess any scratches would be less visible?

thanks
Click to expand...

Yep, I've got a thought... Like most things, don't try to shortcut it.
When I started, I tried sanding to 400 on the grinder, etch, then hand sand 800-1000 grit, then polish. I tried it with what I consider a higher layer count (400-450), medium count (150-200) and lower count (80-150) and even on the higher layer counts, you can see a difference. After etch, I now hand sand up to 1500-2000, then coffee and then 5000. It doesn't take long to go through this final step, especially at the higher layer counts, but I will also warn you that once you start down this path, it's more noticeable if you leave ANY undone spot.
 
Thanks Weo - Good advice.

I would point out that the OP is doing Damasteel, which is a somewhat different material than regular damascus.

Personally, I get the results I desire with FC, and don't use muriatic ( hydrochloric) to etch damasteel.

I do not like using polishes/pastes to finish any damascus. It will blur the pattern and make a less distinct look. I use it on Japanese blades to attain certain things, but not on damascus.
 
Thanks for pointing that out, Stacy as that didn't make it into my consciousness. Apparently I'm pretending like I know what I'm talking about again.

OP - As Stacy pointed out, while my above method works fairly well on my forged damascus, prehaps the only suggestion that may give you the results you want is to not cut corners.

One of the of the unfortunate things about Radioshack closing is that it was an easy and convenient place to pick it up.

PS- Your short cut sanding method works pretty well on my stabilized spalted maple blocks, but only really with Wa handles.
 
Oops, Duplicate sentiment
 
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FC is pretty cheap and easy to get. Just order the dry powder on ebay and mix at home. The mixing method is in many threads.

Here are three I posted:

FC should be mixed to make a 42 Baume stock solution. You add one pound of crystals to 18 ounces (weight) of water to get this strength - two pounds to one quart is close enough. Let it sit for a couple days. Dilute the working solution from this stock . Three parts water to one part stock is what I use ( that is the same as one pound to one gallon if not making a stock solution).
If you are just making up one gallon, skip the stock solution. If making up a larger batch, one gallon of stock solution is easier to store than four gallons of working solution.

Mix outdoors and don't breath the fumes ( chlorine gas - very bad) when it is dissolving. Wearing gloves and a face shield is a good safety practice. It will get hot while mixing if you don't add the powder slow ..... so add it slow. Mix in a heavy plastic tub. A 5 gallon dry-wall or pickle bucket is perfect.



Approx. 1 pint of water to each pound of FC makes a stock concentrate.
In use it is diluted 2-4 parts water to each part concentrate.


For a gallon of concentrate, , I use a 5# container of dry FC and a gallon of distilled water. Add the powder to the water slow, outdoors. It will get hot, and give off chlorine. Wear safety gear....especially a face shield.

For etching, I mix one part concentrate with three parts water. I store it in the etching tank. The tank is an 18" length of 3" or 4" PVC, with a flange foot plate fitting on the bottom (solvent welded in place), and a pipe cap slipped on and off for a top. These parts are cheap at Home Depot/Lowes/etc. The base flange makes a steady stand. The cap seals snugly. The solution seems to store in the tank harmlessly. It sits outside in the smithy year round.
 
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