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Etching carbon steel die-cutting knife(2003)
Q. We are interested in making flexible die cutting knife out of carbon steel. However, it is not easy to get the chemical for chemically etching out the knife in our country. I have heard of water based or non toxic etching process in one of the catalog of a die cutting knife company from Germany for steel. Do you have any idea what this process is all about. Please enlighten me.
Thank you.Siew Kheng Tan
engraver - Singapore
A. Ferric chloride.Guillermo Marrufo
Monterrey, NL, Mexico
? Please reply the 'exact carbon steel' you are etching?
i.e. blue tempered spring steel, cold rolled, 1095 ?
- Portland, Oregon
February 24, 2016
A. It's likely the non-toxic etching process you're referring to is simply the use of electricity and salt water- there are many instructional how-tos around, and video demonstrations on YouTube that can show you exactly how to do it. Depending on the metal and the voltage/current you use, apparently you can get a pretty decent etch.Matt Lukes
- Aldergrove, BC, Canada
How does carbon content of carbon steel affect ferric chloride etching?February 24, 2016
I'm trying to work out some perhaps more historically-accurate ways of producing pattern welded blades such as those made during the first millennium CE (the Migration Period and later by the Norse) but I'm having a bit of difficulty with a basic question that I hope someone can help me answer:
How does the carbon content of carbon steel affect etching with etchants like ferric chloride?
Historically, the metals mixed to form the patterns were nothing like they are today- no high-nickel or even high-carbon steels; they were very low carbon irons and often had very nearly the same carbon content -- what made one appear different than the other was the phosphorus content. One piece of iron had a lot of phosphorus in it, the other did not and that ultimately ended up with them looking different after etching. But the difference was sometimes quite subtle, not stark and obvious as today's versions are; in fact, contemporary descriptions seem to suggest the pattern would appear and disappear, depending on the orientation of the blade, making it seem somewhat magical.
The few surviving artifacts with original surfaces visible (i.e., not corroded), appear to show one constituent of the pattern is lighter than the other, or one is shallowly etched creating a shadow contrast to the viewer.
I'm hoping to re-create both using different mild steels -- keeping closer to the original very low carbon iron part of the equation, and achieving both the lighter-darker and the one slightly etched parts, respectively.
I've found that indeed different types of mild steel etch differently, but I'm having difficulty with determining just which work best for which combination. I've had some MS remain quite bright in a 5% FeCl3 solution (10 minutes etch time), while others get dark, and still others become pitted to varying degrees. All of these are potentially helpful in achieving the looks I want, but I can't yet sufficiently accurately determine just why one or another is doing what it's doing.
Of course I understand MS is quite variable in its chemistry, but certain products are typically one type or another, so if I can find out just how the carbon content affects the etch, I'm hopeful I'll have a better chance of more consistently choosing the right possible material to start with.
Currently I'm just trying various bits I have around my workshop, but it's extremely time-consuming to weld up a and twist proper test piece to find out how it'll look- one piece of hot rolled plate yields one result and another a different result. It's frustrating because I can't find a common denominator, and I'm hoping the carbon content is it. The trick then would be to choose at least the most likely types of steel and just hope I get something that works.
Thanks in advance.
Sword and Armour Recreation Artisan - Aldergrove, BC, Canada
February 11, 2017
Q. Hi how to make color for etching steel? What's the color elements? I want to know the chemical elements of color.solmaz jahani
- iran- tabriz city
A. Hi cousin Solmaz. More words, please. I, for one, don't understand the question.
Ted Mooney, P.E. RET
Pine Beach, New Jersey