Electroplating Metals How-To

Taylor T.

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Just a cool little trick I figured out a while back. Can you see something strange about this photo?
P5160128

I electroplated the penny with zinc and the nickel with copper so that the colors are switched.


I'll only outline how to do the copper electroplating right now, but if someone if curious how to do the zinc I can explain that as well.

OBLIGATORY SAFETY WARNING:
While this is a fairly safe experiment, you should use common sense, and wash you hands well after you are done.

Materials needed:

A few small pieces of scrap copper

A power source with alligator clips attached (I used an old 3.7V 1000Mah phone charger)

Sodium bicarbonate (baking soda)

A large jar made of something other than metal

Isopropyl alcohol (rubbing alcohol)

Metal polish (optional)

Some water



Instructions:



Fill your jar most of the way with water, and add a fair amount of baking soda. This will act as the electrolyte and make the solution more conductive. (Do NOT use table salt as the electrolyte as it will produce chlorine gas) You want to add enough baking soda that the water is completely saturated and there is about half an inch of undissolved baking soda at the bottom of the jar.

Then attach the alligator clip from your power source to the pieces of copper and dip them into the solution. (don't put in in so far that the alligator clips are under the surface, especially the positive one) Once they are in, you should see tiny bubbles of hydrogen gas being liberated from the solution. This is not really enough hydrogen to be a fire hazard, but it's not a bad idea to have a small fan running to blow it away. Leave this electrolytic cell running for a few hours, or however long it takes for the solution to turn a nice blue color.

At this point, your electrolytic cell is complete and ready for use.

To prepare your piece of metal for electroplating you will need to remove any and all oils and grease from it. This is what you use your rubbing alcohol for. After this step you must be careful to only handle the piece with gloves on or with clean tweezers.

Next, attach the negative alligator clip to the piece of metal, and the positive one to a piece of copper. It is extremely important that you have them hooked up correctly.

Once they are attached, submerge both into the solution, and plug in the power source, After about a minute, remove the item being plated from the solution and move the alligator clip to a different place on the piece of metal. If you don't do this, you will end up with a funny looking spot where the clip was. Put it back into the solution, and wait another minute or so. Take it out of the solution and inspect it. If you see any spots that aren't coated, put it back in. If you are happy with the look, it's done!


Now you can polish it until shiny, but don't over-polish as the copper coating is very thin and you could wear through it completely.

You can use this plating solution as many times as you like. If you ever do decide to get rid of your solution, do NOT pour it down the drain, as this could cause serious damage to your local water treatment plant.

Have fun and be safe!
 

Turtulas-Len

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Would this work on a lead object like those old lead toys that that were popular back in the 40s 50s and 60s, I have some molds and plenty of lead and if the lead can be coated with a safe metal I may make some for the grand kids. Thanks for the post..
 

Taylor T.

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Would it be much harder to do a brass coating?
Since brass is a alloy of copper and zinc, it will not plate them both on at the same time because the two metals require different electrolytes. The only way to get a good brass plating is to actually make your own brass by first plating it with copper, and then covering that with a thin zinc plating. And then, heat it up until the object with a torch until the metals blended together. This technique was actually used by magicians to create a "gold coin" when in fact it was just a regular coin coated it brass.

To plate the zinc layer, you will need to make a separate electrolyte bath. This one made with vinegar (dilute acetic acid) and Epsom salt (magnesium sulfate) mixed together. Toss in a few pieces of zinc, and wait for the acetic acid to dissolve it into solution. Once a fair amount has been dissolved, it is ready to be used in the same way as the copper.

If you are just going for the brass color, you could also try gold plating it. It sounds expensive, but since such a tiny amount is actually plated on, it is really quite cheap. Gold will also not tarnish or corrode like brass does. The only issue with gold electroplating is that the electrolyte bath required is a bit more dangerous and you need to create a gold-cyanide solution, with is very toxic

Would this work on a lead object like those old lead toys that that were popular back in the 40s 50s and 60s, I have some molds and plenty of lead and if the lead can be coated with a safe metal I may make some for the grand kids. Thanks for the post..

Lead is a very difficult metal to get to take a plating, and the electrolytic bath I described in the first post of this thread will not work. You will need a much stronger type such as a copper-cyanide solution, which is, like the gold-cyanide I mentioned above, quite toxic.
 

Taylor T.

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Would this work on a lead object like those old lead toys that that were popular back in the 40s 50s and 60s, I have some molds and plenty of lead and if the lead can be coated with a safe metal I may make some for the grand kids. Thanks for the post..

Just thought of something. If the furnace that you are planning on using to melt the lead gets hot enough to melt a safer metal like aluminum or copper, you could preheat the mold, and pour in a small amount molten aluminum or copper. Swirl the mold around to get the whole inside coated with the molten metal, pour our the excess, let it cool down, and then pour in the lead inside that. The lead will not be hot enough to remelt the copper or aluminum, leaving the protective barrier intact.
 

Taylor T.

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Since brass is a alloy of copper and zinc, it will not plate them both on at the same time because the two metals require different electrolytes. The only way to get a good brass plating is to actually make your own brass by first plating it with copper, and then covering that with a thin zinc plating. And then, heat it up until the object with a torch until the metals blended together. This technique was actually used by magicians to create a "gold coin" when in fact it was just a regular coin coated it brass.

To plate the zinc layer, you will need to make a separate electrolyte bath. This one made with vinegar (dilute acetic acid) and Epsom salt (magnesium sulfate) mixed together. Toss in a few pieces of zinc, and wait for the acetic acid to dissolve it into solution. Once a fair amount has been dissolved, it is ready to be used in the same way as the copper.

If you are just going for the brass color, you could also try gold plating it. It sounds expensive, but since such a tiny amount is actually plated on, it is really quite cheap. Gold will also not tarnish or corrode like brass does. The only issue with gold electroplating is that the electrolyte bath required is a bit more dangerous and you need to create a gold-cyanide solution, with is very toxic



Lead is a very difficult metal to get to take a plating, and the electrolytic bath I described in the first post of this thread will not work. You will need a much stronger type such as a copper-cyanide solution, which is, like the gold-cyanide I mentioned above, quite toxic.

I must not have been fully awake when I wrote that first paragraph. I'll try to write a more coherent version now:

Since brass is an alloy of copper and zinc, you will not be able to plate them both on at the same time because the two metals require very different electrolytic baths. The only way to get a good brass plating is to actually make your own brass by first plating it with copper, and covering that with a thin zinc plating. Then, heat up the object on a hot surface until the metals blend themselves together. This technique was actually used by magicians to create a "gold coin" when in fact it was just a regular coin coated it brass.

Hopefully this one is a little less painful to read.
 

Taylor T.

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Turns out you can also use this method to make metal nameplates! I made this one for a ship model I'm building:
P5130125

I intentionally "weathered" the piece of steel before plating it to make it match better with the rusty ship that it will be next to. If you wanted a more "clean" looking one, you could just use a nice smooth piece of metal.

All you have to do to make this is to stick some cheap letter stickers (found a whole set for $0.97 at Walmart) onto the metal to spell whatever you want it to say. Then remove the stickers after you plate it plate, and it's done! The metal will remain non-plated where the stickers are covering it.
 

Turtulas-Len

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Just thought of something. If the furnace that you are planning on using to melt the lead gets hot enough to melt a safer metal like aluminum or copper, you could preheat the mold, and pour in a small amount molten aluminum or copper. Swirl the mold around to get the whole inside coated with the molten metal, pour our the excess, let it cool down, and then pour in the lead inside that. The lead will not be hot enough to remelt the copper or aluminum, leaving the protective barrier intact.
All I have is a pot used to melt lead for black powder ammo. Thank You for all the information. Somewhere in all my stuff i have a small kiln for crafting copper. I never used it, but I believe it doesn't get hot enough to melt copper just hot enough to shape it easily.
 
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