Etching

I am helping my 11 year old nephew make his second knife ( First attempt won him 1st place at the Fair :-). I want to keep introducing new skills
so the plan is to try etch in a simple design on this knife . The steel is an old leaf spring . Does anyone know what to use as a resist and which acid would work for this application ? Ken Cutt
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Bee's wax will make a decent resist. Paint it on or dip the blade into it while it is fluid, them scratch the design into the wax. I don't remember which acid I used so many years ago, but it may have been nitric
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Gerry wrote:

Then Bee's wax it is . Thanks I will pick some up tomorrow . Ken Cutt
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Resist: Bees wax or the tarry stuff used to paint cut surfaces where tree limbs once attached.
Etchant: Ferric Chloride
These things are sold at electronic supply houses for making printed circuit boards.
In the 1970s in Baltimore I used the wax plus ferric chloride approach to etch a friend's name into his knives - he worked as a cook, and wanted his knives to stay his.
A year later, he was going to work on his motorcycle and was stopped by a traffic cop, who found the knife roll and charged him with carrying a deadly weapon.
The Judge took one look at this 10" chef's knife with BARTLETT etched into the blade with 1" high letters, said that this was clearly a tradesman's tool, and dismissed the case.
Joe Gwinn
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Joseph Gwinn wrote:

Thanks . I don't know of any electronic supply places any where near me but I will start checking tomorrow . Would there be much difference between this and hydrochloric acid ? Ken Cutt
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Radio Shack

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snipped-for-privacy@gmail.com wrote:

No more Radio Shacks here , now the Source . I will check them out . Thanks Ken Cutt
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BA - lots of various companies doing trade in electronic parts and projects. BA is East Coast.
Martin Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Life; NRA LOH & Endowment Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
scutt wrote:

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One can get such chemicals by mail order, from Allied or Newark.
Local stores are unlikely, unless you live in a major urban area.
Ask local electronics nuts where the stores are.

Ferric chloride is not volatile (won't evaporate), is easier to control and is safer, and for those reasons is a standard etchant for steel.
Joe Gwinn
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How does it bite, compared to nitric? Does it undercut? Do you have to etch in multiple bites?
-- Ed Huntress
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I've never used Nitric Acid for etching, so I cannot offer a comparison.
I've etched carbon steel (1095) and high-carbon stainless steel (like 440C) with wax resist and a cotton swab soaked with concentrated ferric chloride solution at room temperature, sweeping over the area to be etched manually. I don't recall how deep it went, but it was not superficial. I recall it taking ten or twenty minutes total, but I was talking as I did it, so I wasn't keeping score.
Joe Gwinn
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Thanks. If anyone has compared it with nitric acid, I'd really like to know.
-- Ed Huntress
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    [ ... ]

    [ ... ]

    Well ... I've used both Nitric and FeCl for etching copper printed circuit boards, and the nitric was far more vigorous -- easy to overdo the task.
    No Idea how either work on ferrous metals, however.
    Enjoy,         DoN.
--
Email: < snipped-for-privacy@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
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I've used nitric and ferric chloride for etching copper printmaking plates. The main difference is that the nitric dissolves the metal and it's mostly gone, while the ferric leaves residue in the bite. For that reason, it's helpful to etch upside down in ferric so the residue falls away. (Prop up non-etching areas of the plate on some small plastic blocks; you might also want to rinse your plate and brush off residue from time to time.)
For copper, the best etchant is dutch mordant (hydrochloric acid + potassium chlorate). Unfortunately, it's both difficult to obtain and rather dangerous. The ferric is the least dangerous of the three. The ferric also has a rougher bite than the nitric. The results can also vary quite a bit depending on the acid strength, both the original dilution amount, and the amount of etching time you've used it for.
Also, regarding the resist, check out some printmaking suppliers. The "hard ground" they sell is a brush-on resist that's thin and easy to draw on, it's also easy to remove with solvent. Try Graphic Chemical and Ink in Chicago. The hard ground will be easier to use than beeswax, particularly if your design has any fine detail.
--
Jedd Haas - Artist - New Orleans, LA
http://www.gallerytungsten.com
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Thanks, Jedd (and Don). Have either of you ever tried it on steel?
I've used it on copper circuit boards but this is the only place I've heard of it being used for steel. I've done some etching in steel with nitric acid, a couple of decades ago, and I learned that you have to use several bites to prevent severe undercutting.
I'm curious both about the speed of ferric chloride in steel, and the way it cuts -- undercutting or not.
-- Ed Huntress
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In the 70's I knew a PCB etching house owner. New a better one later in life... This guy was on top of production - did great stuff and was being pushed for more and faster. He converted his automatic spray machine to something like hydrogen cyanide or the like. He found out one day he had a leak. It misted him as he walked by and had to have his sinuses rebuilt from other parts on his body. He looked like a mess for some time due to the operations.
It worked very well and for a while they just built a plexi shield all around it. Collins Radio was a big contract and IIRC, an audit by them (visit) identified their issue - to much demanding when speed wasn't needed. They paid to get the cyanide system out of there and back to a normal spray. With that, he upgraded to another line and just ran two.
Martin Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Life; NRA LOH & Endowment Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
Jedd Haas wrote:

-
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Jedd Haas wrote:

I think shipping any chemical across a border , post 9-11 would be a nightmare . Now Sunday , holiday weekend and no acid . Nor a line on where to get any . Sadly . Ken Cutt
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Y'know, I've used ferric chloride to etch zinc, aluminum, and copper. But I never thought to use it on any iron-based alloy.
I'm a bit confused about this. Is the ferric chloride actually etching the iron, or just leaching other metals out of the alloy?
The reason I ask is, ferric chloride is chlorine and iron in its most stable dimer state of Fe2Cl6. It can dissociate/reassociate bidirectionally in aqueous solution to/from FeCl3, which is also stable.
So... my read is that it cannot actually etch iron. It can "stain" or "reveal" features in iron by leaching out other metals, thus leaving a distinct marking on the metal -- but not actually removing any significant mass of the "etched" area.
When I think "etched", I think of fairly deep removal of the surface metal -- i.e. "dissolved". My best bet is that your friend's blades felt essentially the same across the "etched" areas as in all other areas of the blade.
Yes? No?
LLoyd
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> fired this volley in

Hmmmm.... maybe I "oops'd" a little. Running the redox again, FeCl3 could dissolve some iron to yeild FeCl2, but it would be darned slow... maybe hours in the solution, unless heated nearly to boiling, and with lotsa agitation.
Was this the case? (I try to learn somethin' new ever day. Usually it's the "wrong" stuff that ends up surprising me.)
LLoyd
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On Aug 31, 6:56 am, "Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote:

Yep. I've etched stainless with FeCl3, it took half an hour to go 5 mils. Turned a sheet of shim stock into custom-size washers that way.
Marking, though, doesn't need much penetration. I've also (accidentally) got a little oxalic acid (used for bleaching wood) on a stainless knife, and it left quite a mark, frosting the surface (which started polished).
Which is best, I wonder: polish the blade, then etch to make a frosty mark, or etch, blue the blade, and polish to make a contrasty mark?
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