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+--- Thread: Doing Something Wrong (/thread-2586.html)
Doing Something Wrong - Eeoorr - 03-17-2015
Hello,
I'm a n00b at metal working. I thought I would try starting off with something simple, damascus etching. I watched a bunch of youtubes and ran off
and got some One Shot drain opener (sulfuric acid). Radio Shack no longer supplies Ferric acid, so went with sulfuric acid. I heated up the bath
water to 150 which kept the baking soda rinse at 105. I only had a metal thermometer, so could check the temp of the acid. I put in two cheep stainless
steel forks, one at a time, for about 40 minutes each, and nothing. All that happened was the forks getting wet. I wiped the forks off first with
fingernail polish remover.
Afterwards, I noticed that the acid source also had metal inhibitors, so guessed that was the main problem with a possible metal problem of the forks be
mostly alloy steal metal.
So, I ran off to get some battery acid instead. I also tried a different metal source. I tried a hatchet. This hatchet had no shine and rusts very easily,
so figured it didn't have much alloys in it.
It took a while, but finally got all the rust off using 320 sandpaper. I made a bath again but this time at 120, and out of the wind. I had heard that you
want the acid around 105-110. I saw somewhere that battery acid from the auto store is supposed to be 35% acid. I read the box and went to their website
and there was no mention of the dilution. So, I did 3.5 cups bottled water, 1.5 cups acid. Then I put the hatchet in the acid.
I could see something was going on. There were a little bubbles and a milky haze coming off the hatchet. I jiggled it quite often to knock some of the bubbles
off. I waited and waited and nothing appeared to be changing. As the day started closing, the temp of the bath, assume acid too, slowly started to drop.
As the temperature slowly dropped, the milky haze got thicker. I kept jiggling it to knock the bubbles off. By the end, the bath was 95, but had more milky
haze than when warmer.
By the time I was done, sun was getting too low, I finally put the hatchet in the baking soda rinse. There was a little his. The entire hatchet turned slightly
darker grey, solid color. There was not an etch anywhere on it. It was in the acid for 3 hours and nothing, but solid grey. What am I doing wrong?
--------------------------------------------------------------------------------------------------------------------
Hi and welcome!
I suspect it's the materials you're trying to etch, the pattern etching produces the patttern because the material is made up of regions of different alloys,
some will remain untouched and others will etch different amounts
Rules are for the obedience of fools, and the guidance of wise men...
(Douglas Bader)
RE: Doing Something Wrong - Eeoorr - 03-17-2015
I don't know if this helps or not about the hatchet, already starting to rust a little from being exposed while inside the house. Here are the markings on the hatchet:
X-X
4
B (backwards B)
RE: Doing Something Wrong - Dr Stan - 03-17-2015
Damascus etching only works with Damascus steel. The items you were etching will not work. See: http://www.thompsonsknives.com/damascus_etching_instructions.html
RE: Doing Something Wrong - Eeoorr - 03-17-2015
Thanks,
I guess there was a minor trivia tidbit missing before I started. Was I at least close to correct with the procedure?
RE: Doing Something Wrong - Eeoorr - 03-17-2015
To expand a little, how do you know if it's damascus steel?
RE: Doing Something Wrong - arvidj - 03-17-2015
(03-17-2015, 08:06 PM)Eeoorr Wrote: ... Radio Shack no longer supplies Ferric acid, so went with sulfuric acid. ...
The stuff from Radio Shack is ferric chloride and is pretty easy to find. I have a gallon of it down stairs for etching printed circuit boards. While googling a vendor for ferric chloride also google citric acid as an enhancement to ... not a replacement for ... the ferric chloride etching process.
Ferric chloride seems to be safe to use but be careful as it will permanently stain most everything it comes in contact with.
Arvid
RE: Doing Something Wrong - Roadracer_Al - 03-17-2015
Damascus steel is a forge-welded laminated steel. Normally, the two types of steel are different in that one has lower carbon, one has higher carbon and perhaps a tiny bit of some other stain-resistant alloying agents such as nickel. Both steels, however contain enough carbon they can be heat treated and hardened.
Damascus patterns are created in the laminating of the steel by folding and and re-welding the steel to itself. Forge welding does not use a filler material like "normal" welding. It's basically the same thing as rolling pastry dough into thin sheets, folding it up, rolling it out, folding it up, rolling it out --- the result is lots of thin layers.
Damascus steel is superseded by modern metallurgy in industry, so the only place it is used, generally, is in knife making. The damascus is either purchased from a knifemaking supply, or forged by the craftsman. It's then ground and polished into a knife shape. At this point, it looks exactly like any other knife.
Etching damascus is how the damascus pattern, which is forged into the steel during its manufacture, is revealed. The differing steels will oxidize at different rates, typically, with the lower-carbon steel creating the darker color of the damascus pattern.
Etching can be done with nearly any mild acid. As Arvid points out, citric acid is one, heated vinegar is another that is commonly used.