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Making Plating "crystals" Grow [Nickel trees]
(2007)I discovered this on the web the other day and am very curious about how deposits like this could be grown. Supposedly these are cast-offs from a nickel plating operation, they form on racks that hold objects to be plated. I would like to know if anyone is familiar with deposits like these, knows the process which creates these, and could speculate what makes the deposits grow in this manner. Thanks all.
enthusiast - Doylestown, Pennsylvania, USA
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They are "nickel trees" and many platers have them decorating their desks, John. Indeed they are no work at all, but a headache. Anyplace where metal is exposed on a plating rack the nickel will start to plate out and just keep plating out. You may be able to bend a piece of wire before plating and get a particular artistic shape.
They are probably bright because of the brighteners in the nickel plating solutions. There may be a more scientific explanation for their shape, but I think it's just the geometry of the current flow: As a nodule begins to grow, the outside of that nodule is closest to the cathode and continues to preferentially grow. I'm not sure why it stops, but I'd guess that when the power is turned off overnight the nodule tarnishes and passivates so that it is not as conductive, so seeding starts at new points and those nodules grow. You didn't say where you found this photo, but it look like we can credit theodoregray.com.
There is an article on the subject, under the title "Nickel Growing in Trees", in the April 2006 issue of Popular Science. Good luck.
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |
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Thank you Ted for the generous response. You mentioned that the geometry of current flow might have an effect on the growth of the nodules. Anywhere I can learn more about this-- the geometry of current flow in the plating process?
Am I correct in assuming similar formations can occur with other metals? Would a different metal create a different nodule structure? I don't know the scale of the sample but roughly how long do these take to develop? Thank you for cutting me slack on the copyright, your credit to theodoregray.com is right. -John
enthusiast - Doylestown, Pennsylvania, USA
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The amount of plating deposited is proportional to the current flowing to that point, and the current will take the path of least resistance. I think nickel makes the most aesthetic trees, but I've seen huge blobs of copper. When growing by accident through the splits in rack coatings, the trees probably take a few weeks to build to what you see. As for scale, the larger nodules are about the size of a pea. I edited my reply (after you saw it but before I received your followup) to make reference to a Popular Science article.
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |
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You can grow shapes a lot bigger than a pea by using stainless steel wire that you have sharpened the points on as the cathode. You could wrap 2 - 3 in one group facing away from each other.
It results from the extremely high current density at the point plating many times faster than a part. Many times it is caused by a sharp bur or conductive spec on a part. It is common at the intersection of a part and its masked edge.
- Navarre, Florida
Sorry that my reply was confusing, James. Yes, these trees can be good paperweights and are much larger than a pea. John said he had no sense of scale from the photo and I meant that the size of the largest individual rounded bumps or nodules in his picture might be about the size of a pea.
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
First of two simultaneous responses -- +++++++
I once did a fun little project.
I had some silver wires from some old spent pH electrodes somebody was throwing away...with the idea that I'd get some solid silver billet electrodes, I put them in a 500 ml Hull Cell, filled it with cyanide silver plating solution, and turned the power supply on just as low as it would go. Then I went out of town for 6 days.
When I came back, I had grown these...silver twigs. They had a grainy, "organic" appearance. Really sharp looking. I made each one into a pendant (I fiddle around with jewelry sometimes) that got lots of admiring comments.
You could do the same thing with an acid copper solution (far less toxic) and get all kinds of fun shapes by plating little twists of stripped bell wire in the same way.
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Dave Wichern - The Bronx, New York |
Second of two simultaneous responses -- +++++++
Take a bunch of copper wire and twist them together for a couple of inches.
Open out the strands and trim to a rough cone.
Plate with nickel for a day or so(chrome works very well too).
Welcome to the world of platers xmas trees. But don't let the boss see you, he will want one.
Or; Take your nodules (copper is good for this) Choose one with a relatively flat back. Solder on a small loop of wire and gold plate. Great pendant for your favourite lady.
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Geoff Smith Hampshire, England |
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Do the deposits have to happen at a burr or edge? Let say I was plating a smooth hemisphere. Would it eventually produce this kind of growth? If not, what if the surface of the hemisphere was perturbed in some way, how would I perturb the surface to begin producing deposits?
John Bersethenthusiast - Doylestown, Pennsylvania, USA
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Most plating will eventually grow very course and nodular, especially if the solution has no brighteners, and especially if the current is too high for smooth plating. Good luck.
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
+++++(2007)
Hi,
I've posted on the forum before [see also letter 45277] on the subject of nickel trees or aggregate deposits created by extended bouts of plating. I think I now better understand what factors influence where deposits form
(position of the anode, the degree of curvature of the cathode object.) I'm attaching an image of the kind of deposition that I write about.
Now I'd like to try to learn a bit more about what determines the actual shape of these deposits. I'm hoping to see if some variation in the electrolyte would make these deposits more branchy or dendritic. I believe the shape of these deposits (the degree to which they are either nodular or branchy) has to do with the throwing power of the electrolyte. Is this correct, does the throw of an electrolyte have an effect on the shape an aggregate deposit takes? Are there baths for copper or nickel plating that have limited throwing power?
John Bersethenthusiast - Doylestown, Pennsylvania, USA
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The second lot of pictures are typical of what we call a dog-bone effect. Since current always takes the path of least resistance, the nodules growing on the edges is typical of nickel.
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Khozema Vahanwala Saify Ind  Bangalore, Karnataka, India |
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John, these things look like tumors! What are you going to do with them?
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Sheldon Taylor supply chain electronics Wake Forest, North Carolina |
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To research and predict the growth of nodules, I suggest that you start with the mathematics of chaos theory and finite element analysis.
Let us know how you get on.
Good luck.
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Geoff Smith Hampshire, England |
October 17, 2010
Hello,
I was wondering if John Berseth had any results or some research to share?
Best,
Gregory
- Geneva, Switzerland
October 18, 2010
Hi, Gregory. John hasn't been back for a few years, and most people's email addresses go out of date quicker that that. People usually come back when they do an internet search and see their name. So describe your own situation or post your own question, and chances are good that you'll start an interesting dialog, while also keeping the page fresh for good search engine placement so John will eventually stumble upon his posting again :-)
Letters 37080 and 25979 also cover this subject. Good luck.
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
October 24, 2010
Hi Ted,
Thank you for the reply.
Here is my project:
I have this architecture model made out of bronze casting. (For information, its the Palace of Culture and Science in Warsaw).
And next Tuesday I will bring it to a local electroforming company here in Poland. There it will be copper plated for as long as possible to create dendrite formations similar to the photo of John above in this discussion.
Now based on the model, what are the advices you could give me? Would it be interesting to have the model rotating while in the bath? or just change the position once in a while during the process? Are we talking about 3 days of plating? 3 weeks? What are the crucial things I should tell the plater?
I know I will get answers by trying, but I was wondering what was your opinion about it.
Take care,
Gregory
- Geneva, Switzerland
October 25, 2010
Hi, Gregory.
Realistically, the hands-on copper electroformer is probably going to know more about this than I do, and probably won't appreciate 3rd-party advice from someone who has never seen his shop, his tooling, or his capabilities anyway :-)
But, yes, I think it should be periodically rotated every couple of hours. Judging more from when good electroforming goes bad than from deliberate attempts to build copper trees, I think 2-3 days of plating in a bath with no brightener will produce the desired results. Other readers may have a better feel for it. Best of luck!
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
January 12, 2011
Hello Everyone, this is exactly what I have been looking for.
My one simple question is, could you do this kind of electroplating using a battery pack of AA or 9V batteries?
I am working on robotic growth, and intend to use electroplating to allow the robot to grow.
Please let me know if anyone knows how to electroplate using batteries.
Thank you!
- Winnipeg, Canada
January 12, 2011
Hi, Jake.
Plating with batteries is not much different than plating with a power supply except for two things, the inability to control the voltage (without inserting power-wasting rheostats or resistors in the circuit) and the fact that a battery won't last long.
Depending on what you are plating with what, something like 3 volts will be enough. But recognize that a battery and a plating tank are pretty much the same thing operating at reversed polarity. Your battery must provide enough voltage and then some to force the plating tank to run as a battery in "the wrong direction". Then think about the fact that there is no such thing as perpetual motion, and you'll appreciate that a battery can't power any more plating than empowered by its own deplating. For a quantitative answer to the idea I'm presenting, see Faraday's Law of electrolysis, from which you can calculate how many ampere hours are required to deposit a given amount of plating. Penlight and 9V batteries only have the power to do a very little bit of electroplating. Good luck.
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
January 13, 2011
Thank you so much for your reply and the great information about the Faraday Laws of Electrolysis.
Could you take a look at my concept for robotic growth here and let me know if you think it would work?
I am trying to create a rod by "growing" it using electroplating, each time the buildup is significantly thick, the rod is moved out so as to expose more area for the rod to plate up - in theory, would this work?
Jake Middleton- Winnipeg, Canada
January 13, 2011
Hi, Jake.
Well, yes, it could work "in theory". But really? Sorry, but I doubt it. Most plating has a limited thickness due to such factors as: the tensile or compressive stresses become so severe that the object lacks real mechanical integrity; the plating becomes too porous as small lumps grow on big lumps and you don't get plating down between them. With a carefully engineered cell, with plating solution jetted at the surface, it might be possible to repeat your steps a few times and build a few mm of rod, but as a practical way to do continuous extrusion, I don't think it looks very hopeful. Good luck.
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |