Metal Plating part or all of a plaster sculpture

[k-man]

Hi everyone, I'm a sculptor/Grapic Designer.
Recently I've been using plaster as my medium of choice, however, I have some ideas I'd like to execute in other materials. one of them being metal.
I've seen on the website that it is possible to metal plate plaster using a sealent, followed by a special silver spray paint. I find this very exciting and want to know what the success rate is of a procedure like this.
any input would be greatly appreciated.

Thanks,
K-Man

[tubby]

copper over plaster

I do some work in stone and plaster also. I have developed an interest in making some copies of some of the very old statuary on some grave markers and have been reading up but will make my first plating effort next week. This is what I have been told by others to do. Dry plaster in oven for several hr at low temp 175f or lower. cool and seal in a sodium silicate solution by immersion at least two times. allow to dry 2-3 days then apply a silver conductive spray allow it to dry 24-36 hrs then electro coat with acid copper. If you find any better wqay or errors in this method please post and I will check back. The silvaspray may be to expensive on a large casting so I am checking on several carbon conductive coatings that look promising for testing. Good Luck

Tubby Toby

[gsw3]

Tubby, good ideas and the sodium silicate is about as safe to use as you can get.

For larger, less intricate items I have found a 2-part polyester resin primer works great also.
This primer has to be sprayed on, thus good for larger parts that are too large to dip or brush.

Prime the part with Duratec Sanding Primer #707-007.
It is available at well stocked automotive paint outlets (body supply shops).

This is a (2) part polyester resin primer that works great, however:
The disadvantages of this primer are as follows:

 Precise mixing is required.
 Gel time in the gun is approx. 15 minutes.
 Extremely toxic substances are used and personal protection is a must.
 It is much harder to sand.
 Because of its hard to sand nature, it does not lend itself to small detailed parts.


Mixing and application instructions for Duratec Sanding Primer #707-007:

1. Start with (2) ounces of Duratec sanding primer #707-007.
2. Add (2) ml of MEKP (Methyl Ethyl Ketone Peroxide in Plasticizer).
3. Add (14) ml of MEK (Methyl Ethyl Ketone).

Mix vigorously and spray immediately.
Material will gel in approximately 15 minutes.
Clean gun immediately with MEK.
Will set up hard in about (2) hours

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So you don’t want to mess around with the toxic stuff the above?
Want to try something that is not water soluble like sodium silicate?
Your plaster casting can also be sealed by following the instructions below:

(THE PLASTER MUST BE 100% DRY!)
Also, check to be sure the solvent in your conductive coating is compatible with the shellac before doing the final piece.
Try a test piece first!

1. Thin white shellac at a 1:1 ratio (use denatured alcohol for the thinner) and immerse the part in the thinned shellac solution under about 16 to 20 hg. of vacuum to totally impregnate the plaster.
2. Keep it under a vacuum until hardly any bubbles are escaping from the part.
3. Release the vacuum, pull the part out of the solution and allow the excess to drip of.
4. Take a few paper towels and wipe off and drips of shellac.
5. Let the part dry for 3 days (don’t force dry) and coat with a conductive coating of choice.


Just a couple of alternate ideas to try.

GSW3

[Maxxx]

I have a little experience with what you are planning on trying, I tried to cover it as best I can here:

http://www.caswellplating.com/bbs/viewtopic.php?t=2916

Basically, it's not very easy, but you can do it. Plan on spending a LOT of time hunched over an acid copper tank, especially if you piece is complex in shape. The simpler, the better, period. If you part is really smooth and flat or nearly flat, I would try the copper leaf. If not, paint or copper powder. Good luck!