Electroforming or Plating with Gold, Silver, and Other Metals

Electroforming or Plating with Gold, Silver or Other Metals

We get two questions more frequently than any others about electroforming and plating. This post is to answer both of these questions and to offer some new information about plating with various metals using the E3 Duo Controller. 

This question more than any other: Can I electroform with silver or gold? The answer is yes you can.  Since electroforming in silver and gold is rare for the home studio, it is more likely that when people ask about electroforming, they really mean to be inquiring about plating. Both processes will be explained below:

Electroforming is traditionally done with copper and then plated later with other metals.  For practical reasons it would be massively expensive to electroform in pure gold or silver but it is possible. Also, gold and silver are relatively soft so it would take a lot of precious metal to form a strong layer over an object. Typically cyanide based gold and silver solutions are used for electroforming because the cyanide keeps the metal suspended in solution for long periods of plating. There are YouTube videos (mostly by commercial labs) and books out there on the subject if you Google electroforming with gold or silver.  To do this you would simply substitute gold or silver for the copper anode and use the appropriate plating solutions.

Gold and silver is most commonly achieved by plating which is covered in my 2nd topic below.

Will the E3 Duo Eform Controller plate other metals such as gold and silver?

The answer is yes. Simply use the controller in place of a rectifier and set it to a low current level while plating. Most plating solutions only take a few minutes. Each metal calls for different steps, solutions, anodes, equipment and safety concerns. Plating takes quite a bit of training and knowledge so be sure to research the steps of the particular metal and solution you want to use before committing to plating.

To give a brief overview of plating, plating is the process of applying a thin layer of metal over metal. To prepare a piece for plating the piece must be cleaned with an electro-cleaning solution and then dipped in acid prior to plating. The piece must also be rinsed between solutions to avoid contamination. The piece then goes through a series of steps involving heating and agitating the solution (if called for) as the metals are plated. If I were to get serious about plating different metals I would invest in a plating station unit like this one below because it provides heat and agitation to certain beakers where needed: 

http://www.riogrande.com/Product/Midas-Six-Station-Plating-System-1-Liter/331961?Pos=6

Certain metals cannot be plated over one another without a barrier layer of metal between. For example a layer of nickel should be plated between copper and gold to keep the gold from migrating with the silver. RioGrande.com has great charts on their website which can be found with each plating solution to show you the steps in order for plating. Here is an example of the information offered with the 24K gold cyanide solution: 

http://www.riogrande.com/Product/Midas-24K-Gold-Cyanide-Based-Concentrate-Plating-Solution/335082?Pos=9

Along with knowledge of the steps and becoming familiar with the characteristics of each plating solution, the most important consideration is SAFETY. When you get into plating various metals you can be dealing with very dangerous chemicals. 24K gold is available in non-cyanide and Cyanide formulas. The cyanide is what makes the gold so rich and beautiful. But it can be fatal if misused. You need to wear a NIOSH mask, proper gloves, apron, goggles, and use a fume hood for ventilation just to name a few of the safety precautions.  If you go to Rio Grande’s website and study each plating solution it will make sense what is involved for plating. This is not a casual craft.

With all of this said, our controller is meant for the small jewelry-making studio for electroforming and plating on a small scale.  I electroform with copper frequently and then I plate those pieces with various metals occasionally. This piece was a leaf that I electroformed with copper and then it was plated with nickel followed with 14K gold.

Successful Shiny Copper Plating: Get the power going first!

It's so important to turn on the power on BEFORE you submerge your piece in the copper plating solution!

Look at the unicorn toy on left, it was in copper plating solution no power for the first 5 minutes. The horse toy on right had power and current flowing right from the start!  Both toys were left for several hours to electroform.  The horse built a heavy layer of shiny copper, the unicorn never really formed other than a thin dull coat.

I’m always learning something new about electroforming and plating. This weekend Dan and I were electroforming pieces with copper and I put a prepared piece (covered with sealer and water-based graphite paint) into the copper plating solution without turning on the current. I left it there for about 5 minutes before turning the controller on. The result wasn’t good. The piece didn’t plate very well and the copper was a very dull salmon color. The next piece was a similar charm (small rubber toy) prepared in the same way. This time we turned the controller power on and the current was set to HIGH. The prepared piece was then submerged to begin the plating process. We left it on high for just about a minute and then set it to a medium setting until finished (several hours to electroform). The result was beautiful. The copper was bright and shiny with a thick deposition of copper. After several experiments we discovered two important things: 

1. Always turn the power on first and then submerge the piece into the solution while the current is flowing.

2. Start with your controller set on HIGH for about a minute to get the plating started. This will expedite the coverage of the copper over the graphite paint. Since the graphite paint is water soluble, this boost in current minimizes the amount of graphite that might flake or soak off had the piece been left longer before plating. We also think that the boost in current helps to limit the contamination to the solution that occurs when organic materials are electroformed. Even with a boost in current, organic materials still need to be sealed very well prior to applying conductive paint and plating.

I found that by making sure the power and current were on prior to plating, my solution stayed viable for many subsequent pieces.  I only had to add a few drops of brightener after plating 5-6 pieces.

Electroforming Question: Why is my piece dull and not plating?

Electroforming is easy, yet there is a lot to learn.  One of the most FAQs we get is: Why is the copper plating surface not bright and shiny? What am I doing wrong? This happens after plating a few pieces. It's frustrating because it's hard to understand why this suddenly happens when previous pieces plated just fine. The good news is that you can polish it to a high shine because it is simply rough copper. But make sure you formed the copper thick enough before sanding or polishing. Here is a pdf to explain why copper can look dull and how the acids are depleted from the plating solution, even after electroforming just a few pieces. The easiest answer is to buy new plating solution.  However, read this to understand the reasons why:  Maintaining your copper plating solution

Edited to add:
We also have a new video about how to shine up your piece with a brass brush and polishing pads!

Electroforming Tips - Keep it Moving, Keep it Warm

On a recent visit to the studio of jewelry artist Nancy Worden, she was gracious enough to educate me on some of her valuable tips for electroforming. Nothing can replace the years of experience she gained through her labors, and with plating there are no easy shortcuts. I am anxious to pass along a few vital steps I learned from her:

KEEP IT MOVING: Agitation reduces the sharp and uneven build-up of copper particles on your piece. This is especially true for pieces that are left to be electroformed for long periods of time. If you have ever left a certain piece to build a heavy layer of copper for a long time, you may have noticed that the edges or protrusions feel sharp or rough. By providing a way to circulate the free floating copper particles, the result will be more rounded edges which do not feel as sharp. It may be of interest to note that Polypropylene anode bags also play a role in keeping the particles from forming sharply.
A simple solution? An Aquarium air pump. To make your own bubbling device, drill holes in a piece of tubing to be fitted to the pump. In this photo you can see how a slightly larger tube was drilled and fitted over the longer green tube which fits snuggly to the pump. The end with holes in it is placed in the electroforming solution about 30 minutes to an hour after the initial coat of copper is formed. Turn the pump on to provide agitation for the remaining time necessary for electroforming.

KEEP IT WARM: Optimal temperature for electroforming copper is between 75 and 80 degrees fahrenheit. Nancy Worden has found through years of experimentation that this produces the best results. You can use warming devices such as an electric heating pad to heat the tank, especially in winter. Use safety precautions when using electric devices near water.

MAINTAINING THE ELECTROFORMING SOLUTION: There is no easy answer for this one. This can get very complicated, and frankly dangerous, if you start adding acids or experimenting without some knowledge and respect for electrochemistry. Artists like Nancy have their own protocol for maintaining and attending to the plating bath. As every situation is unique, you have to take responsibility for deeper education and study. There are pdf's and books online that are written for associated products from the plating industry for detailed information. You have to decide at some point whether the goal for using the solutions is for a personal hobby, mass production, or an industrial studio set-up. The latter involves getting to know the chemicals and developing a personal knowledge for how and what to do to keep the plating solutions clean and filtered, and the ph levels even. Most solutions sold for small studio or hobby use are sold with the premise that they will be used until exhausted (at a certain coverage rate) and then replenished as needed.

SOME METALS DON'T PLATE: With any art or science like electroforming, there are always new things to learn. One thing I learned recently is that there are certain metals which will not successfully plate with copper without pre-treatment. Steel, iron, or metal with tin in it will not plate well.

 - Sherri

Etching on Silver

Dan and I spent some time this weekend experimenting with silver etching using the E3 Etch controller. Here is the story with our findings, we are both pretty excited about the results. To start with, we are using a chemical called Silver Nitrate for etching silver. This worked better than other chemicals we tried and produced nice etchings. This is available in powder form and it is not harmful unless large amounts are ingested, so you have to keep this away from pets and children. It is extremely bitter, which helps that situation, but you should educate yourself on safety. The other caution is that it will stain your skin if you touch it. And I’m not kidding, look at my fingers! All I did was touch a few specs of it as we were measuring and pouring the crystals out of the container.

This won’t hurt me, but I am stained now for a good 2 weeks. I am shooting how-tos for a book right now with close ups including my hands, so now I have a lot of photoshop work to do. I suggest you wear gloves when working with it. Other than staining skin, it doesn’t produce fumes or pose an enviromental hazard in the small amounts we are using here. It is sensitive to light and air, so keep it in a bottle in a dark cupboard between uses. And, like the copper sulfate we are using to etch copper and brass, you can use it for a long time. With sterling, the solution will weaken over time as copper from the sterling dissolves into the solution. With fine sterling this shouldn’t be an issue. Simply strain it through a coffee filter and store in a plastic bottle-PET type (Marked with a POISON! label so no one drinks it).

To etch the silver, we mixed 10g. of silver nitrate with 1/2 liter of distilled water. The first piece we tried was sterling silver. The piece was sanding and then I wrote on it with a fine Shapie oil paint pen, it’s the little square that says “Dan & Sherri”. We etched this piece for 30 min on slow and it etched pretty quick. If left longer, the etch would have gone deeper. The silver etches about 3-4 times faster than copper does. The second piece was a PMC standard silver clay heart bead. This piece was originally overheated and melted a bit as it sintered so the outside was rough and bumpy. I wrote on this one with an extra fine Sharpie oil pen. I put a bent aluminum wire through one of the holes to suspend it and provide contact. I taped around the edge and sealed the back. I found it easier to “hang” the piece rather than using foam spacers because it didn’t have any sides to attach the spacers. Since it was a curved shape with a bumpy surface, I filled the the pan with enough etching solution to cover only the part I wanted to etch. The tape was used mainly to keep the piece level in the solution, and not as a barrier for the solution. We found that the wooden chopsticks did a great job to hold the wire. This piece was etched for 2 hours on slow speed. It was much slower than the sterling piece as it is larger and was suspened quite a bit higher from the bottom of the pan. When removed the metal clay has a very “crystaline” structure where the metal etched away. As soon as the piece was rinsed off and burnished the background was pretty smooth. I need to experiment more with PMC3 or + to see how they compare. This photo shows the set up for etching on the fine silver bead. Now that we have this figured out, I need to make some “wearable” pieces with cool designs.

PMC standard on left, Sterling on right