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topic 0085 p.5

Copper electroforming problems

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A discussion started in 1995 but continuing through 2019

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

August 27, 2019

A. Chuck Jansen:

That's a really ugly copper deposit. It's going to take more than some brightener to make it useful.

I suspect you have used some poor quality chemicals.

If you really want to pursue this, contact a supplier of plating chemicals; a few of them deal in hobby-sized quantities.

jeffrey holmes
Jeffrey Holmes, CEF
Spartanburg, South Carolina

Bright acid copper over electroformed copper?

August 16, 2019

Q. Pretty quick question... I've been pretty good results with my electroforming, but it is a little dull. Can I use a bright acid copper bath to build up the thickness and then hit it with a polishing wheel? Or should I be working the amps and timing to get a better finish from the bath? Thanks

Ray Walker
- Salt Lake City, Utah

August 28, 2019

A. Yes, you can use a bright copper bath, but the deposit will be less ductile. This may or may not be an issue, depending on end use.

jeffrey holmes
Jeffrey Holmes, CEF
Spartanburg, South Carolina

September 3, 2019

thumbs up sign Thanks for the feedback Jeffrey, the piece is just meant to be decorative so it being less ductile shouldn't be a problem.

Ray Walker [returning]
O.C. Tanner - Salt Lake City, Utah , USA

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