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topic 0085 p4

Copper electroforming problems

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A discussion started in 1995 but continuing through 2019

January 7, 2017

Q. Hello, I have a few questions.
1) How do you correct your copper solution if you have an organic contamination?
2) Also, how do you know when the pH level needs to be changed and how do you do so?
3) I use graphite paint and Midas copper electroforming solution. I've used this on silver, brass, copper etc.
I've seen silver conductive paint and solutions and it's way more expensive. At what point do you use those? Am I not supposed to use the graphite paint and solution on metals other than copper?
Thank you!

Zoey Kemp
- Kona, Hawaii, USA

Copper Plating Solution

Copper Plating Solution

Copper Plating Solution

March 12, 2017

Q. Hi there,

I just started electroforming jewelry and had some success in some success. However, recently my pieces have been coming out not copper toned but salmony. I've already replenished with distilled water, and added more brightener. I also tried Dremel polishing and steel brushing the piece to try to bring out the copper colour but it just made it a shinier salmon colour … can anyone tell me why I can no longer achieve the rich gold tone?

Thank you!

Justina Lee
- Vancouver, BC, Canada

June 17, 2017 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. I have a piece I am electroforming. I need to leave and wondering if I can turn off rectifier and come back to it later? If so, can I leave it in the solution, or should I take out, rinse and let sit?

Thank you,

Rebecca Hawks
hobby, jewelry designer - Oceanside, California

June 2017

A. Hi Rebecca. We appended your inquiry to a thread about electroforming of copper. Please confirm that you are doing copper electroforming from copper sulphate because, while that would probably be okay to interrupt, other processes like nickel electroforming would be ruined by such interruptions.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

June 21, 2017

thumbs up sign Yes, I am electroforming with copper electroforming solution

Thank you!

Rebecca kenney [returning]
- Oceanside, California USA

Copper electroforming pinholes, grooves and flaws

October 15, 2017

Q. I am dong some copper electroforming on a small scale at home for a model engineering project. It is going quite well but I have trouble with the apparently random formation of odd little grooves, a few thou deep, sometimes connected to a pinhole. They are up to an inch long(usually shorter) and tend to run vertically. I can sand them out but this adds to the work.
I am using a standard acid electrolyte with levelers, chloride, etc., all to a known recipe. Current density is about 50 mA per sq inch. Total required thickness is approx. 0.5 mm and area of the cathode is 42 sq inch. I use anode bags but have not been using phosphorised copper, to save money. I have no way of analysing the bath.
The base material is a low melt tin/bismuth alloy which is melted out afterwards.The cathode shape is simple and smooth with no holes. The final copper sheath is strong enough and appears OK but needs a bit of sanding work to get it smooth. I can fill the worst flaws with solder and plate over but this is a nuisance.
Any ideas? Also can someone please tell me where the agitation bubbles should be placed relative to the cathode?

Many thanks

Stephen Wessel
model engineer/hobbyist - Shepton Mallet, UK

What copper plating solution for electroforming 150 µ thickness?

November 30, 2017

Q. Dear Sir
I want to do copper electroplating on polyurethane foam with more than 150 micron thickness.
What kind of bath solution do you propose? because, Most of copper electroplating solutions are used for less thickness.

Faezehe Barzegar
- Meshad, Iran

December 19, 2017

Q. Hello. I'm just getting started and have done 2 pendants so far. The first one came out great and super shiny. The second next one came out dull! Even after trying to polish and put in tumbler. I did change the anode from a small sheet to copper wire coiled inside. The wire seemed to have a flaky layer coming off it and there also seems to be copper powder moving through solution. The wire and all my supplies are from Rio Grande. I have another in now and it's looking alright so far … but not shiny at all! When do you add brightener? I strained through coffee filter but how often does this need to be done? Also filtering through carbon?

Andrew smith
- Winston Salem, North Carolina

January 23, 2018

Q. I have been playing around with electroforming small pieces of jewellery. I have successfully electroformed a ring and some earrings onto metal. I then tried out a conductive graphite paint specifically made for electroforming and it is not receiving the copper correctly.

My graphite paint test was on a leaf. It was first sealed with acrylic sealer that came from the same company as the graphite paint, left to dry for 24 hours (as stated in the instructions) and then the graphite was applied. The graphite paint seemed to pull the sealer off and leave an uneven finish in places. I left the paint to dry for another 24 hours (again, as instructed) and put it in the bath using the same method and amperage as my successful tests onto metal previously. The graphite seemed to come off into the solution a little and I could see little floating clouds of copper after a short while. After 10 hours (a lot longer than I had left the first test for) I pulled the leaf out and only a small amount of copper had transferred over and only where the conductive wire was directly touching and areas next to it.

My set up is as follows; Rectifier set at ~ 0.3 amps and 0.7 v; positive wire connected to a copper pipe resting across the bath with 1 mm copper wire hooked on with object to be electroformed fully submerged. Negative wire connected to two copper pipes in the bath. Looking at some diagrams I think I may have my positives and negatives the wrong way around. Is this detrimental to the process? If so, why was I able to get a successful test directly onto metal?

My real question is, what am I doing wrong. I believe that the paint and all of the chemicals are of good quality and I feel that the process isn't working due to my lack of knowledge. Is there anything in my process that screams out?

Looking for any advice.
Thanks in advance.

Min Cawthorne
- Bristol, Somerset, UK

May 9, 2018

Q. I have had success electroforming pieces in the past, but recently when I have been putting a piece in the bath the copper will only collect on the copper hook I have attached to my jewelry piece and not the piece itself. My jewelry pieces often consist of crystals coated in graphite paint.

I have an electroforming tank with a copper solution that I made myself:
For 1 gallon of distilled water-
32 oz. Copper Sulfate
32 ml. Sulfuric Acid
10 ml. Brightener

I'm not sure if this is my problem, because I have successfully plated pieces before with this solution, but I can't think of what could be the problem because I have not changed anything else in the process.

Any help is appreciated, thank you!

Kara Cimmarusti
- Chicago,Illinois, United States

Can electroplating rectifier be used for electroforming?

July 7, 2018

Q. I have access to three "old" Vigor electroPLATING controllers. Can these be used for electroFORMING? If so, what should I know about cross-purposing them?

Jann Greenland
- Little Rock, Arkansas USA

July 2018

A. Hi Jann. If they are in working order they should be fine. The biggest difference in electroplating and electroforming is just the name :-)

We call it electroplating if we put a metal coating on an object, for example a truck bumper or circuit board. We call it electroforming if the plating layer itself comprises the object, for example a hollow gold earring formed on a wax core or a stamper for vinyl records formed on, then removed from, the lacquer master. If you're doing a gold flower, some people will call it a plated flower and others will call it an electroformed piece of jewelry.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

July 17, 2018

Q. Hello,
I am hoping to use an older electroplating rig to do some electroforming on jewelry pieces. The problem is, the electroplater has only a single control knob. It has a DC Volts meter and a DC Amp meter, but only the single control knob. (It's an HR Superior 10 Amp Electro-Plater)

In my first test, I had the machine turned up about 20%, the volts showed zero, the amps constantly fluttered between 0 and 2. The copper that was deposited on the piece was flaky and had poor adhesion. The solution also heated up substantially during the process and I'm unsure if that's normal.

Do you have any advice on using this machine for electroforming or do I need to shell out for a more modern device that has independent v/a controls?


Wil Aarons
- Cambridge, Massachusetts, USA

July 2018

A. Hi Wil. Ohm's Law says V = A*R, so there actually is no such thing as independent control of voltage and amperage anyway, although it is true that more sophisticated control systems might let you pick a particular amperage and have the power supply increase/decrease the voltage as necessary to hold it.

It's possible that an old unit is defective, of course, including the possibility that the voltmeter which read zero is broken (you probably only need 1 or 2 volts for your electroforming). But you could start troubleshooting by reading the voltage it's putting out with an external voltmeter. If the solution is heating up (which is normal), it is because of the power the rectifier is putting into the solution.

If you're certain that you have good connections to the anodes and the parts, yet the amperage is jumping all over, it may well be defective. But there are many possible causes for flaky & poorly adhering copper, and the rectifier is not the first place I would look unless there is good reason to believe it is bad.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

July 26, 2018

thumbs up sign Thank you so much for your response! It turns out that my entire plating supply died later the same day I wrote. I sourced a new power supply and my electroforming is now working just as I had hoped.

Thank you again. I am finding to be an excellent resource!

Wil Waychoff
- Cambridge, Massachusetts USA

Need a Rectifier Substitute

August 29, 2018

Q. Hi, I'm interested in starting electroforming copper jewellery but I cannot find a rectifier anywhere. Are there any substitutes for a rectifier?

Dani Putter
- Johannesburg, Gauteng, South Africa

August 2018

Plating/Anodizing Power Supply
0-15V 0-5A

A. Hi Dani. Your problem is surely not unavailability of plating rectifiers, but language differences such that you are not recognizing that available power supply devices qualify as what people are calling 'rectifiers'. You simply need an adjustable power supply which, depending on the size of your jewelry, can provide perhaps 5 Amps (or probably even less) at about 0-6 Volts (most offer higher voltage, but the lower the better). Good luck.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

September 11, 2018

Q. Hello. I make electroformed jewelry and I make my solution myself. Everything was going smooth till last night. I left the rectifier open on a low current to plate a pendant in a 1L solution. Current was about 0.2 amps and voltage was about 0.3 I think. In the morning most of the piece was plated the way I want but a small part of it was left above the solution (I don't know how but it evaporated more then usual I think).

And the part left outside looked like it was plated a thick layer of textured copper but when I touched it, It just crumbled. Not even crumbled, it was all squishy. Then I electroformed one more piece and same thing happened to the whole pendant. Why do you think it happened? Can someone help me please?

Cagin Ucar
Chitta Studio - Turkey Canakkale

September 2018

Trouble in Your Tank: Handbook for Solving Plating Problems
by Larry Durney
from Abe Books
info on Amazon

A. Hi Cagin. When you go from satisfactory plating, to unsatisfactory, keep in mind Larry Durney's 'Logic of Troubleshooting':

"We can safely assume that a working system cannot become a non-working system without some change occurring"

In this case I think you're already 99% confident about what changed: the solution composition -- perhaps due to evaporation, extended run time, or something else. But you've not yet given us any information on that subject. Although it would be nice if people could tell us how to solve the problem of squishy plating from solutions of unknown composition, I don't think that's likely to happen. Get back to us please.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

September 13, 2018

A. Probably too low amount of copper. Maybe iron in solution can be cause too. Try fresh solution. Hope it helps and good luck!

Goran Budija
- Zagreb,Croatia

September 20, 2018

Q. Hello. I am having a problem with getting any substantial amp. readings or plating occurring. I have a 7 gallon tank with all Technics equipment. I'm running copper foil test pieces in the tank. 3 @ 3"x 3". I have the volts up to 7.5 and it is only pushing .5 amps. The pieces are salmon colored. I hadn't used the set up for over 6 months, much of the water evaporated so I replenished it with distilled water. Copper anodes were out of the tank during this time.

Any ideas? Thanks

Jamie Bennett
- High Falls, New York

September 2018

A. Hi Jamie. Put the leads of a V-O-M directly on the anode and your test pieces to insure that the problem is neither with the rectifier nor dirty connections. If the pieces are receiving anywhere near 7.5 Volts that should be way more than enough, and probably quite excessive -- which means that the problem is the anodes or the solution.

I don't know what you have in the way of chemical analysis or test equipment, but if you do not have a Hull Cell and you aren't able to do any analysis, and cleaning the anodes doesn't help, you might be limited to replacing the solution. Good luck.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

October 1, 2018

Q. Hi, I am trying to electroform with copper but when I pull it out of the bath and rinse it off, after drying it seems to develop a bright rainbow iridescent finish. any idea why this may be?

When electroforming with copper, are there certain shapes that are easier to "burn"? I have been trying to electroform a pinecone. I wrapped a wire in a coil around the pinecone and it seems to keep turning matte brown. other things I've had in the bath at the same time however have turned out fine so I'm assuming it has something to do with the shape/ surface area or my wrapping technique?

Kiersten pappas
- columbus, ohio, united states of america

December 6, 2018

Q. Hello! I'm quite new to electroforming (about a month) and I'm grateful to have come across this forum :) I've managed to work through a lot of my problems through research and trial and error but the latest problem is really stumping me.


I set things up and mixed my bath according to Jason Welsh's methods. I have his book and I've watched a ton of his YouTube videos. The bath is made with distilled water, root killer as the copper sulfate, and battery acid (not using a brightener). It's about a half gallon of solution, and so far I've been making small pieces, surface areas in the neighborhood of an inch or so.

The problem I'm having is that instead of getting a nice thick coating over time, my pieces will get a very thin coating and then develop these super sharp copper 'spines' all over. Not a very friendly texture for jewelry!

Maybe I'm not using the right terms in my Googling but I'm having trouble finding any information on this phenomenon. I did read something to suggest that sharp textures could be the result of copper-oversaturation, so I tried diluting with distilled water & sulphuric acid, but the next piece still came out spiky. I'm at a loss for what to try next!

Any clues would be very much appreciated!

Emily Gomez
- Denver, Colorado, USA

December 2018

A. Hi Emily. Jason has great instructor skills, speaking slowly & clearly, and repeating things.

But some important points:

-The right way to electroform is with properly formulated addition agents including brighteners. Although brightener is expensive, almost all platers and electroforming shops uses it to prevent the "treeing" you illustrate.

- Electroforming faster (higher current), although it will not prevent treeing, may at least encourage "lumpy" trees rather than "spiky" trees because they'll "burn" away before they get quite so thin.

- Jason has a youtube video titled "Electropolishing Copper, the End of Brightner (sic) in electroforming" where he acknowledges these trees and removes them.

- A really important point, though, is that Jason is very good at liking the look he gets :-)

Wavy, lumpy, uneven electroforming may be fine for the stuff he's doing, lending an artistic one-of-a-kind appearance; and it may be a fine look for your items too -- it's a matter of what you're looking for. But electroforming without brightener, and then trying to fix it by electropolishing or tumbling the spikes back to lumps isn't for precision items. Try to even imagine a stamper for vinyl records or CDs made by these methods.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

January 5, 2019

Q. Hi, I am fairly new to electro-forming and before I ask my question I want to make any potential answering members aware that I have no interest in mysterious pre-made chemical solutions as far a solution for my problem is considered.

First off I am working with a home made solution derived from Jason Welshes free Youtube tutorial (copper sulfate) and my electrodes are high purity copper. Now my Problem is that I have not been able to achieve a shine on any of the pieces I've electroformed. They have all come out of the bath with a flat salmon color and have poor adhesion. I Have tried different levels of current, this only changes the texture of the deposits. I have also added a simple home made brightener (polythylene glycol) into the solution after I carbon filtered. I don't have a pH meter so I cannot determine if the solution is of the correct pH but I do know that I have not added much in the way of water to it and I'm sure it has experienced evaporation. I plan on adding some distilled water but if that doesn't help what are my options?

Ethan Rowlette
- hamilton, Ohio, united states

January 2019

thumbs up sign  Hi Ethan. Everyone is very welcome to choose their own interests; no problem at all that you want solutions that don't involve proprietaries! But since I've already said that I feel it's the only way to go, and you've clearly stated that you have no interest in going my way, peace then :-)

Hopefully another reader will address your questions in the way that you wish.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

March 12, 2019

Q. We are setting up a 20 amp rectifier to a 5 liter tank and it has been a nightmare to find instruction on how to set Amps and Volts. We often find contradictory advice. There is a fine and coarse dial, but what do we do first, turn on Amps and adjust Volts or the other way around? I've read 0.1 amp per square inch and 1 to 2 Volts but not sure in what order to do this. We have tried electroforming with turning Amps up until Volt reading was 0.5 and and Amps read 0.2 an hour later turned Volts to 0.6 and Amps went up to 0.3 but not much plating occurs on 5 square inches of surface.

Breeta Toma
- San Jose, California

March 2019

A. Hi Breeta. Although you'll never get away from finding contradictory advice, understanding the principles is a good first step; then you can decide what seems reasonable and try it :-)

(courtesy of

The thing is, amperage and voltage are not independent; they are completely locked together by Ohm's Law:
Amps = Volts / Resistance

Any given setup will have a given electrical resistance based on things like the pH, concentration & temperature of the solution and the distance between anode and cathode. Then if you increase the voltage, the amperage will increase; if you decrease the voltage, the amperage will decrease proportionately. Some power supplies let you control amperage -- but when you do that, you are choosing to control the amperage and letting the the power supply put out however much voltage it needs to in order to deliver that much amperage.

It sounds like your particular power supply has a switch allowing you to control by voltage or amperage, and then a pair of course & fine adjustment knobs which do the double duty of controlling either the voltage or the amperage depending upon whichever you selected with the switch.

If the area of your part is 5 square inches (remember to include both sides), and you want to try plating at 0.1 Amps/square inch, set the switch to Amps, adjust the knobs until you read 0.5 A (which is quite low for a 20 Amp rectifier) and the voltage will adjust itself whatever it needs to, probably to a volt or two.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

March 21, 2019

thumbs up sign  Thank you so much, and the graphic is especially helpful. Had my first success and think we'll be off and running. We set the Volts at 1.5 and that did the trick.

Breeta Toma [returning]
- San Jose, California

Adhesion problem with Copper electroplating/electroforming

March 30, 2019

Q. I'm hoping someone with more experience than I may be able to shed some light. I am very new to electroplating and enjoying this experimental stage however I'm not getting great results thus far.

I am endeavouring to plate copper rings with gemstones. I have used epoxy putty to mould the stone to the ring base and once dry coated that with a conductive paint. (It's worth noting I have tried both a home made graphite paint and a commercial one with the same result)

For the power source I have two 1.5v batteries with alligator clips - negative to cathode positive to anode.

The bath is copper sulphate.

I have a copper coil anode inside the bath.

The piece to be coated is suspended via a copper wire wrapped on a dowel (wood).

My problem is the plating - after several hours the tiny copper particles are attracted to the cathode but just form a muddy layer that doesn't really stick.

I must mention I have tried several different power sources, bath solution strengths and anode pieces. I'm getting the same results each time.

Any wisdom is greatly appreciated. I do apologize for the long post but wanted to provide all the information.

Dannelle Guihot
- Batemans Bay, NSW, Australia

March 2019

A. Hi Dannelle. A hobbyist/experimenter like yourself is unlikely to have any substantial analytical tools with which to troubleshoot ... yet you need to start figuring out whether the problem is the plating solution and your operation of it, or something to do with the ring and putty and metalizing process.

So I think the thing to do is to get a nice piece of brass (maybe an old key?), clean it thoroughly while wearing gloves, rinse it, acid dip it for activation, rinse it, and attempt to plate it. Once you can plate it fine you can move on to trying your ring again. Good luck.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

April 10, 2019

Q. Have just filtered my electrolyte to try and fix this problem, still the same issue.
My parts are a wax mold painted with conductive copper paint.
Solution is 3 gal distilled water, 2.5 pounds copper sulfate 1 pint sulphuric acid, using regulated power supply in constant current mode -- same results when 1 amp or 2.5 amps.


The parts copper deposit is very grainy or nodular and kinda crumbly.
What am I doing wrong?

Charles jANSEN

April 18, 2019

Q. Try 200 gms copper sulphate/ 30 ml sulphuric acid / 1 lit distilled water solution. Use copper wires only.
Cathode anode distance 10 cm at least. Keep current density as low as it is possible. Hope it helps and good luck!

Goran Budija
- Zagreb , Croatia

April 19, 2019

3 gallons of water would require 5 lbs of copper sulfate and 1.43 cups of sulfuric acid.

I also see some forums saying to use brightener... What is that?

Chuck Jansen [returning]
VINTAGE MUSEUM - Machesney Park, Illinois

April 2019

A. Hi Chuck. Yes, your 5 lbs and 1.43 cups for 3 gallons sound right, but I think you'll have to get comfortable with "grams per liter" rather than asking people from Europe to convert their answers to pounds per gallon and cups per gallon for you because those are terms that many of them have probably never even heard :-)

Goran's numbers would be for 96% or 100% sulfuric acid, not battery acid -- what you are using?

"Brightener" means organic addition agents which shield the high current density areas from plating in order to smooth, level, and brighten the plating. It's usually not a generic chemical but a system of proprietary ones from a vendor of acid copper plating solutions. Some people, like Ethan Rowlette above, and Jason Welch in his youtube videos, are confident that such addition agents are unnecessary; others, including me, think you should buy a proprietary copper plating solution from a vendor of proven solutions rather than trying to formulate your own plating solutions.


pic of Ted Mooney
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"

April 22, 2019

Q. Yes I am using battery acid as it is what was listed in the recipe I had found on line.
The density of both the copper sulfate and the acid were about half in my recipe compared to these suggestions.

Will be looking for a source for the brightener.
Then the question will become how much of that to add.

Chuck Jansen [returning]
VINTAGE MUSEUM - Machesney Park

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