Electroforming

[Maxxx]

Does anyone here have any experience with electroforming on non-conductive items with acid copper? I had this idea to form on a really hard clay by painting it with copper paint. The copper paint covered well, but was not conductive enough, only the first half inch plated. I was thinking about wrapping the piece in copper foil, but I wasn't sure if the areas where the foil would overlap will "fill in". Thought I would ask before I make anymore mistakes

Anyone have some experience with this? I was also thinking about rubbing the surface with copper powder.

[Maxxx]

Nobody has tried this? Well, I bought a copper leafing kit, I'm going to give it a try tonight.

[shadetree]

Maxxx, let us know how it turns out though .

Shadetree

[Maxxx]

The leaf was definitely conducting well, but it still didn't work. The leaf is so thin that I think the acid in the bath dissolved about half of it before it could plate, the rest was plating well. I think I'm going to try to try it again, but nickel plate it first to protect the leaf, then copper plate it.

I'm guessing silvaspray would work well here, but I was trying to avoid the pain of the whole thinning paint and spray gun process if I could since I'm just doing a couple small pieces.

[Maxxx]

Well, my plan kinda worked. Applying copper leaf to the clay part and then nickel plating was successful. I then plated in the acid copper. The nickel did a good job protecting the leaf, so I didn't see the deterioration this time. However, I don't think this is going to be the way for me to go. The part I want to form over has some complex shapes, and the leaf wants to bunch up and wrinkle a lot. I'm not really sure how well the copper would "fill in" the gaps and wrinkles, so I think I'm not going to risk this on my clay elephant I spent 3 days carving . I think if you had a very simple shape, the leaf would work great, but for me, I think I need paint.

Next step (and probably last try), silvaspray...

[Coley]

electrofoming cups

I am in the process of setting up to electroform some lightening ball cups. Metal stampings are too expensive to make a deep draw die for so will try forming over wax patterns...
I am trying a copper powder spray for the primary coat....

[Maxxx]

What kind of copper spray are you using?

[Coley]

It is a spray you mix up using just the copper dust and lacquer thinner. You coat the part you want to plate with a clear lacquer and then before it gets dry you spray the copper /thinner mix on it. Then put in the acid copper tank and plate to the thickness you want.
I made up a refillable spray can today rather than use a paint spray gun. I use air pressure to charge it.
As soon as I get the copper bath ready I will see how it works. I have a lot of small parts to electroform.

[Maxxx]

Where do you get the copper powder? I've had a hard time finding it.

I have finished two parts using silvaspray. I made a part out of very hard clay (I think it’s called plastilina or something like that), then put on three coats of clear lacquer to fill in any porosity. I then brushed on three coats of silvaspray. It worked, but not quite as well as I hoped for the cost. One thing I learned is that it would not plate acid copper directly to the silvaspray. I tried it several times, with zero success. It would take nickel rather well, so I would have to strike coat with nickel over the silvaspray before I went to the acid copper.

The first part I did was probably too complex of a shape to get really good results, an elephant, but even in the areas where it should have worked fine; I had had a lot of missed spots. It just wouldn't plate evenly. I had to go bad and repaint with silvaspray in those areas, then nickel coat the whole thing again, then go to the acid copper. Had to repeat that process several times, but never did get some areas to plate very well. I was planning on leaving the finished part as a copper finish, and maybe put a patina on it, but it looked so uneven that I just put on a final layer of nickel since it covered much better.

I did a much more simple part the second time, a spoon, which turned out much better. However, even this simple piece had some thin areas in the copper. I will post a couple pics today.

What I take away from this experience, and I admit that its very limited experience, is that you need TONS of conductivity for this to works. I would think that a copper powder layer might work better, the copper leaf definitely worked great, but covering a compound curved surface without wrinkles is impossible. Oh well, I had an interesting experience and made a couple of unique Christmas presents, now onto nickel plating the bolts on my motorcycle!