Sciencemadness Discussion Board

Anyone here familiar with electroforming?

gnitseretni - 14-1-2008 at 09:50

Is there anyone here familiar with electroforming and has made their own electroforming solutions? I'd like to try copper electroforming. But instead of buying a copper solution, can I make my own with copper sulfate and drain cleaner?(I got both) And if so, how much would I use of each?

I've searched google and although I did find that they use copper sulfate and automotive battery acid, I can't find any ratios. Does anyone know?

Your help will be appreciated.

microcosmicus - 14-1-2008 at 10:34

Try a saturated solution of copper sulphate in a few percent
sulphuric acid. For this and other information, see
Henley's recipe for electrotyping:

http://chestofbooks.com/reference/Henley-s-20th-Century-Form...

I haven't tried this myself, so I would be
curious to hear how it goes for you.



[Edited on 14-1-2008 by microcosmicus]

12AX7 - 14-1-2008 at 11:14

Useless without a few drops of thiourea solution (Tarn-X contains it).

The concentration and all isn't very critical. A few drops of Tarn-X (filter the soap scum that precipitates), enough copper sulfate to make a 1/3 to 1/2 saturated solution, and a splash of acid for whatever reason (presumably, to dissolve impurities).

A much deeper mystery is, how to put the copper on the object? I've heard conductive paint (including metal flake, graphite, etc.), mirror process (usually silver, I don't know if you can even make a copper mirror deposit), etc.

Tim

BromicAcid - 14-1-2008 at 13:59

Using the forum search engine you can find our somewhat lengthy thread involving electroforming, somewhat cryptically titled "Electroforming is Useful"

http://www.sciencemadness.org/talk/viewthread.php?tid=1990&a...

gnitseretni - 14-1-2008 at 20:19

BromicAcid: thanks for the link. Since I'd like to spent my time actually electroforming and not altering the solution just to make it work right, I think I'd be better off just buying a solution instead of making it myself.

12AX7: They use conductive paint to electroform onto non-conductive objects. If you ever need some.. http://www.safer-solutions.com - I got this source from the following webpage which gives some insight on how to electroform copper: http://www.katefowle.com/pages/tips.php

garage chemist - 17-1-2008 at 17:24

I want to make nickel sheet by electroforming onto a flat cathode from which the nickel plating can be peeled off later.

I thought of using lead sheet as both anode and cathode, and nickel sulfate solution as electrolyte.
In sulfate solutions lead can be used as an insoluble anode since it passivates with PbSO4 and PbO2- I have tried this myself before.

Lead cathode because the lead can simply be melted off after the nickel deposit has been made, or else dissolved in e.g. dilute acetic acid because it forms a short-circuited galvanic element with the nickel.

Does anyone have experience with electroplating thick nickel deposits? I have read up a bit in Ullmanns, they add boric acid to the electrolyte and use nickel chloride as well, but I want a sulfate-only electrolyte so that I can use a lead anode.

I'll probably do the experiments concerning this myself and find out what works for me.

I want to try this because industry actually uses this to make sheet nickel without using standard metal working methods like hot-rolling.
If I can come up with a way to electroform nickel sheets myself, it would be a great help for everyone who wants to build a Castner cell for sodium production.
I don't have access to sheet nickel as well (only have a really thick slab of electrolytic nickel, way too thick to be of use).

12AX7 - 17-1-2008 at 19:51

I got this from a friend:

Nickel plating levelers, first degree: Saccharin, aromatic sulfonic acids.
Second degree: butynediol, coumarin, ethylene cyanohydrin, formaldehyde.

I bet butynediol is stinky...

Lead will probably stick to nickel, I wouldn't recommend it. Stainless steel and titanium I think are the usual substrates.

The BEP (Bureau of Engraving and Printing, part of the U.S. Mint) prints bills by engraving plates, embossing them to a plastic substrate, then silvering the substrate (probably the traditional silver mirror reaction) and plating nickel on that. After some cleanup (trimming and grinding), the nickel sheet then goes to the printing drum.

Right now, I'm plating copper onto a titanium substrate, and it seems to be coming out relatively level. We'll see if it's solid. Earlier, I was plating on a copper substrate, which resulted in a botryoidal deposit. I'm not getting any of those really cool shiny, globby dangly-bits like Theodore Gray has in his collection (chrome, nickel and copper IIRC), but I do have some neat pieces.

Tim

garage chemist - 17-1-2008 at 20:15

I have p-toluenesulfonic acid and formaldehyde. If the plating turns out bad, I can try adding some of those.

Are you sure that stainless steel and titanium are better substrates than lead when I want the nickel plating *not* to stick to it?
I have titanium strips, is degreasing with acetone followed by cathodic degreasing enough for pretreatment so that the nickel coating turns out even?

12AX7 - 18-1-2008 at 04:52

Hell, I'd intentionally touch it, just to make it release better. With titanium that may not be a concern though. Grease should affect the evenness though...

Tim