Copper plating aluminum enclosure experiment results

[John Lyons]

I had read about copper plating here from Joe Davisson a while back.
I emailed him and he gave me the "recipe".
The main ingredient is Copper Sulphate Pentahydrate which can be found in "root Killer"
which is used to kill roots in septic systems and drains.


Here are a few of my results:



I started with the bottom lid. This color was acheived with three separate plating baths.
You can see definite copper plating and a nice earthtone color but since enclosures are zinc
and aluminum alloy blends you can see the paterns in the finish.
The plating chemicals are also granular so you get a bit of variation and splotching which can look nice.







This is the same process but with much different results.
I used too much of each chemical here (as with above) but if you follow a more strict process
you should get better repeatability. I was just testing out what the posibilities were....







This was with about 4 baths worth of the same procedure.
Not sure how the blue and purple came out that way. I like this one though.







I was working on an experiment with salt water etching and had a container of orange copper scum from doing that.
I figured that if I reverse the etching process (switching the electrods polarity) with that setup I could plate the copper
settled on the bottom of the container onto my midnight blue box from above...
It worked. The copper can rub off a bit so you need to be careful. Most of it stays though.







I got impatient and put the copperplated box in a container and just speckled the top with the chemicals and then sprayed them with a spraybottle filled with water and left it for a while. There are a few different colors in the finish here. I repeated the speckling and ended up with this. Heat plays a part in the process so I heated it up with a heat gun while it bubbled away.







I brushed on a couple coats of amber shellac and now it looks like this.
All of the experimenting here was with one box so going from a bare aluminum box may produce different results.

Here is the process and recipe:

Dissolve 1/2 a teaspoon of "Root Kill" (mine was called "Root Killer" by the cmopany Roebic) into enough boiling water to cover the aluminum box. The chemical you want to look for in your product is Copper Sulphate Pendahydrate which will be blue granules and about 99% pure.

Lower the box into the water and allow it to reach the same temp as the water and rootkill temperature.

Stir in a large dash of "washing soda" (Sodium carbonate, can be found as Arm and Hammer "Super Washing Soda" in the supermarket etc) which is  dry fine granules. I'd say I put in a teasspoon spoon or so.
A small dash of Cream of tartar powder can be added as well. (not sure if this is doing anything so it may be optional) Cream of tartar is a cooking ingredient used to make various things.

Stir in a little more washing soda and Cream of tartar until the box is plated. (I have found that the main reaction took place with the initial addition of the washing soda and nothing much noticable happened after that. I left the box in the solution for 10 minutes or so. Agitating a little and spooning over the solution to dry areas.
The plating will rub and scratch off a bit while you are working so it's best to be gentle and handle the box as little of lightly as possible until the plating is done. I also cleaned the box with acetone to remove any oils and finger prints.

Rinse the box in water and let it dry. When you get something you like you should clear coat it to preserve the color and metal brightness.

As always, wear rubber gloves and work in a well ventilated room. Be carefull!

Thanks Joe for the details!

John

[Steve Newton]

Love it!

The copper blue colour is beautiful. A real winner if you can nail down a repeatable chemical mix and application procedure.

And that speckled finish is wonderful. How's that for antiqued visual mojo? I like the un-shellacked version better, I'd be tempted to leave the plating to age and discolour even more.

[birt]

i was experimenting ith the same thing but you have far better results. i need to find the time to experiment more.

there's  some nice possibilities like etching a design and then copperplating the etched lines or copperplateing and then etching graphics.

[GibsonGM]

Another step in the process could be using the root killer bath, and trying actual electroplating, using a copper pipe and the inside of the aluminum box as electrodes.  Might be worth a try - I read somewhere that that is how they electroplate aluminum...the solution adds more copper.  Or, are you already using electrolysis in your process? Didn't see that mentioned.   Most sites I've found talk about using 12v, 500mA or so, I've been wondering how it would turn out using the root killer.   Without the extra copper solution, the results suck...I tried it without, lol. 

[John Lyons]

Good one. I've been reading up on plating as well. I plated the copper on the straight copper looking photo using saltwater etching but with reversing the leads. Positive on the copper piece and negative on the piece to be plated. Haven't tried it with the copper sulphate solution yet.
Fun fun Fun!

John

[Rick]

Just a few words on what I've learned about electroplating die cast aluminumn metal. Well I have been in an electoplating shop for just over a year and I've done silver, zinc, tin, copper, nickel, and yes cadmium plating (i'm in canada, it's not against the law yet here). What we use on aluminum before even attempting any plating is what is called "zincate" solution (just 3 mins of soaking in this is all it usually takes)  It will allow the copper to be bonded to the aluminum beautifully -solid copper all over. Then we can plate it with most any metal. Copper takes most every plating metal (zinc, nickel, silver, tin, etc)  It is for sure near impossible to get good results plating anything on die cast aluminum boxes without this solution ! You'll only end up with severe blistering. Play with the other ideas for sure, as you may just end up with some really nice blistery antique effects!

Zincate solution - probably gotta' be a chemical supply house ....................Rick

[John Lyons]

Thanks for the insight Rick. There was another thread about this stuff and it mentiones zincate as well.
I'll have to buy some and do it right.
For now I'm digging the mottled look. I like the many colors and randomness.

What solution does the shop you work at use as a medium for plating? (not the metal plated but the liquid the parts are submerged in)  or does is depend on the metal?

John

[GFR]

Ain't Copper Sulphate a really, really toxic poison?

[rocket]

No, it's slightly poisonous, you're going to vomit if you swallow it.

It is harmful to water organisms though. It need to be disposed as as chemical waste and not just be put into the sink.

[brett]

Hi
Copper is definately not good to put into wastewater.
Land disposal is relatively safe for the small amounts discussed here (it's used in garden fungicides - aka Bordeaux mixture coz they've used it in southern France on grapevines for hundreds of years).

The weird blue/black colours might be monovalent copper (Cu₂O) (wild guess).  It doesn't look much like the more familiar forms of copper: pinkish metal copper (Cu) or blue divalent copper (CuO, CuSO₄).
cheers

[John Lyons]

The "Root killer" product is sold as a treament for septic and drain sytems. It's not nuclear waste but it's not harmless either.
The chemical is the same as in the garden treatment mentioned above but it's much more pure. 99% copper sulphate pentahydrate in fact.

John

[Rick]

Basicaudio, I'll look at the copper tank tomorrow for the list of chemicals it contains. We have two tanks for copper: copper strike, and copper plate. Strike is done for just a minute of plating for a base coat, the the copper plate for 2-3 mins depending on the thickness required. Most often though the copper is only used as a base for plating silver or tin.

[brad]

I wonder if you could label the box by masking areas prior to plating?  Perhaps you could even etch labels with ferric chloride before plating too.  That would look pretty crazy.

[brett]

I wonder if you could label the box by masking areas prior to plating?

That's easy to do.  The metal is delivered by low voltage Redox reactions.  Simply mask using an insoluble non-conductor.  (Nikkko, paint, tape...)

[John Lyons]

You should be able to do the press and peel/photo paper toner transfer thing here as with normal etching. Iron on your lettering and etch, then plate would = recessed lettering you could blaken. Or Iron on, then plate which would leave you with aluminum/silver colored lettering or any graphic.
With the darker colored "plating" the silver lettering would look nice!

John

[amz-fx]

Copper sulfate is fairly mild stuff...  it is sold in aqueous dilutions to add to swimming pools to prevent algae growth...  but you still want to be careful with it, and it will stain metal surfaces in your sink if left exposed to them!

regards, Jack

[Rick]

Basicaudio, I had a quick look at the label on our copper plating tank and it lists: potassium hydroxide, cyanide, brightener / carrier etc. and the copper anodes of course. The parts to be plated are connected to the negative lead, and the power is applied from a couple of amps for a few small pieces to like 60 amps for surface areas of several sq ft. There is a lot of cyanide used in many of the plating and cleaning tanks (ie: copper , cadmium) but not in the zinc, tin, and electroless nickel tanks, so when the parts are cleaned in ~50% HCL they must be rinsed very well in several water tanks before going into the plating tank as HCL + cyanide = hydogen cyanide and we surely don't want to turn the place into "the gas chamber"! I can give you more info on the ratios of chems and names of the brighteners if you want to go pro, but cyanide scares most people off.

[John Lyons]

Thanks for looking that up Rick. I think at this point I'm going to go with either a zincate bath as a base for copper plating and doing the method I used in the pics. I like the distressed look of old tarnished copper and the mottled look of the two pics above. I usually build wood boxes so this is just a diversion/distraction for now.

John

[zjokka]

Great experiment!
Certainly got a aged feel to it..

zj

[calculating_infinity]

Great job John!  Beautiful enclosure!

-Jonathan