Electro Plating

[f350ca]

Hoping someone has more experience than me. Shouldn't be hard. lol
Wanted to nickel plate some parts on the model engines Im making. Seamed like a simple enough process so gave it a shot.
From Utube videos mixed a bit of salt in 5% vinegar and dissolved nickel strips to make the plating solution. Worked like a charm using a 12 v battery as a power source.


Tried plating a copper strip with good results, sorry poor phone camera, but in a minute or less got good coverage.
Fine but how do I know if I'm plating steel when they're verbally the same colour,


So thought I'd copper plate first then nickel plate.
The internet showed a few different methods using baking soda, muriatic acid or again vinegar to make the electrolyte. So I tried vinegar today.
Used copper pipe to form the solution again using the 12v battery, Quickly got a beautiful blue solution.



With the nickel strips the positive anode dissolved and the cathode stayed relatively clean while making the plating solution, nickel acetate.
With the copper the anode turned white and the cathode developed a layer of copper coloured paste, easily wiped off.
With the copper acetate made I tried plating a steel rod. The videos all seamed to use lower voltages with copper so tried using the 3.3 V output from a computer power supply. Quickly get the same copper coloured paste forming on the cathode. But it just wipes off the steel rod, no plating actually bonding. Even tried a D cell battery thinking the voltage had to be lower, same result. 12v gives the same result only quicker.
Sorry no photo of the rod but this is the same material scraped off the copper cathode when making the solution.



Any thoughts? Could I have dissolved too much copper in the solution? It got quite warm during the process.
Im all ears.

Greg

 

[markba633csi]

I think you have to add hydrogen peroxide- I'll post a link

High Quality (and Safe) Copper Plating

High Quality (and Safe) Copper Plating: There are a few copper electroplating methods on here, but they are either dangerous, provide very low quality results, or cost an arm and a leg. Your plated object should be a brilliant, shiny red, not blackened, and your pocket book shouldn't be …

www.instructables.com

 

[RJSakowski]

Copper will plate out on steel with no battery involved. I used to plate copper out of ferric chloride solutions used to etch copper on printed circuit boards by just putting some steel bars in the spent etchant. The steel was oxidized as copper was plated which probably is the cause for your poor bonding.

I seem to recall a high school chemistry experiment where we plated copper onto steel but that was more than sixty years ago and I don't remember any details. If you look in a chemistry text, you should be able to find some suggestions.

The overwhelming consensus on the web is that copper plating steel can't be done but there are many examples of successful plating. Steel MIG wire is copper plated, as are electrical grounding rods. Years ago when automotive bumpers were chromed, they were made from steel, first copper plated, then nickel, and finally chrome. The problem is that it may require some chemicals that aren't easily acquired. I guess I would try using a copper sulfate solution with some additional sulfuric acid. You might try a small reverse bias on the battery. It's counterintuitive but it may slow the plating down sufficiently that you would get a good plate.

 

[f350ca]

Will try another mixture with hydrogen peroxide tomorrow. The first site I found used just vinegar so stopped looking there. Wonder what the hydrogen peroxide does?
What does the internet know RJ? Yes copper plating steel is common.
One I looked at used muriatic acid to form the copper plating solution. Wanted to stay away from this as I recall reading fumes from muriatic acid are very corrosive and can cause flash rusting on tools in the shop. Is that true or am I not remembering correctly as is often the case.

Greg

 

[francist]

Wanted to stay away from this as I recall reading fumes from muriatic acid are very corrosive and can cause flash rusting on tools in the shop. Is that true or am I not remembering correctly as is often the case.

Yes, that much I do know, and from personal experience. It will rust anything (ferrous) within a good sized radius given half a chance. Even plastic jugs that you’ve opened but then sealed again seem to somehow leak enough of the fumes to cause rusting. I still have the acid, but it lives outside now well away from any tools or machines.

 

[brino]

Wanted to stay away from this as I recall reading fumes from muriatic acid are very corrosive and can cause flash rusting on tools in the shop. Is that true or am I not remembering correctly as is often the case.

I fully agree with @francist!

I had some in the shop and noticed things rusting near it.
I moved it out to the shed still in original plastic jug, then double bagged and in a bucket..... still had problems.
Moved the whole thing outside.

Brian

 

[markba633csi]

I had some 36% HCL in the corner of the garage, unbeknownst to me there was a tiny hole in the jug. You better believe that
caused some corrosion problems- lost a micrometer because of it, seized it up so bad I had to toss it

 

[durableoreo]

Caswell has some good how-to type documentation. They also sell all the reagents you might need.

 

[RJSakowski]

I find the above posts re: HCl rusting interesting as I have had a jug of HCl sitting in my basement shop for the past forty years and I don't experience the rusting problems that others seem to. Maybe the brand I buy has a better container. My jug sits under my basement sink which is about 15 ft from the nearest machine. I may have better ventilation as well as my basement foundation is 110 y.o. limestone and mortar with plenty of chinks.

I dilute the concentrated acid about 1:1 with water if I'm using it indoors which cuts down significantly on the obnoxious fumes and it I want to use it full strength, I do that outdoors.

If you suspect that you have HCl fume leakage, pour a little ammonia into a shallow dish. and set it nearby. The ammonia vapors will rapidly react with any HCl vapor forming a telltale white "smoke" which will settle on nearby objects, forming a fine white powder.

I worked in various lavs over my career and we kept our acids along with the ammonia under the fume hood. There was some indication of the white ammonium chloride fumes in the cabinet but little indication elsewhere. The first lab that I worked in used to dissolve manganese dioxide in concentrated HCl in 500ml beakers. The procedure was to combine the two on a hotplate and boil them until the manganese dioxide dissolved, adding more acid it necessary. There would be fifteen to twenty of these beakers on the hotplate every day. With the high volume of HCl being used, literally gallons each day, the inside of the fume hood was coated with the white powder but very little outside the hood. OTOH, we also digested samples with concentrated sulfuric acid. When all the water is removed, sulfur trioxide, a dense white vapor, is the result and even though it was in a fume hood with the window closed, small amounts of the vapor would escape into the room.

 

[rwm]

After having a metal shelf rust away I came up with this. I store my acids in sealed bottles inside heavy ziplock bags. In each bag I put a porous bag filled with sodium bicarbonate. The theory is that the bicarb will absorb and neutralize small amounts of acid vapor. So far, so good. Is it possible that limestone in a basement neutralizes acid vapor?