- TUTORIAL - Bronze electro plating - Do your own Bronzo!

[JohnPilot 11]

This little tutorial describes my own experiences with bronze electroplating. I did a lot of try and error and want you mostly to get aware of the possible errors and things not to do.

 

I have to write this

When you want to try this tutorial be aware that it may be wrong or faulty. You work at your own risk. I take no responsiblity.

 

Some times pictures do not correspond 100% to my writing, this means I have updated my procedure.

 

Feel free to comment and ask questions.

 

 

(This is my way to do it. If you are afraid of my way using alot of chemistry you can try simpler.

Basically you only need an electrolyte, can be salted water or even coke, it must pemit electricity to pass through. So no destilled water!

You need an anode. it will be a piece of the marerial you want to plate, here bronze. Then a source of continues 12V electric current, can be a car batterie or a car battery charger. A large bowl or bucket and you are ready to try out. The watch case you want to plate will be your cathode.)

 

 

What do you need for bronze plating?

• tank which can consist of a plastic bucket, the electrolyte is not corrosive
  
• electrolyte
  
• caustic soda
  
• brake cleaner
  
• 2 bronze anodes, plates of the material you want to plate, maybe copper, nickel …
  
• fish tank heater
  
• fish tank air pump
  
• 12 V auto battery or charger, better a variable source of continuous electrical current
  
• copper wire +-3m
  
• crocodile clip
  
• hydrochloric acid
  
• dishwashing detergent
  
• pair of gloves, very clean without traces of any dirt, grease or talcum
  

The technique in itself is very simple. You use electric current to transport the bronze from the anodes (+ positive pole) to the cathode ( – negative pole) which in this case is a watch case placed into an electrolyte. The electrolyte is a liquid conducting electric current and with this very small bronze particles. These bronze particles will form a thin deposit on the cathode, watch case, the plating. You will be able to determine how thick you want this plating to be.

 

 

 

We use a plastic bucket with a lid containing +- 6 liters. This bucket is filled with 4.5 litres of distillated water. Now we need to make the water able to conduct electric current. We do this by adding metallic salt (inorganic salt). You can buy different kinds of this salt depending on the kind of plating you want to do. While adding the salt we stir with a stick and notice that the liquid’s temperature rises to about +- body temperature. Now we have our bucket filled with electrolyte.

 

Then we place the two bronze anodes into the bucket. Most anodes have already a hole in which we fix a copper wire. Pull off part of the insulation (about 5 cm) and pull the not insulated part through the hole of the anode and fix it with a knot. These wires will be fixed at the + pole of our 12 V charger. To vary the voltage we can use a simple resistance wire or better a variable power source. I used the wire. By cliping the positive crocodile clip closer or farer to the outlet, we can decrease or increase our voltage.

 

 

 

 

 

 

 

 

Our cathode will be the watch case fixed with a wire to a plastic tube put over the bucket. To this wire we will fixed later on the negative - pole of our charger.

 

Now we have set up basically our tank.

 

 

 

 

 

 

 

 

Plating color and density depends on several factors. This allows you to influence the result.

The electrolyte should be at least +25 C° (it works up to +60C°). The hotter it is the lighter the plating color will be. Here comes our fish tank heater. You can buy those at +-20 euro and they heat the water to a temperature between +24 and +34 C°. This is important when you plate in your garage or work shop where the temperature can be lower than +24C°.

 

When plating you get better results if you stir the electrolyte or move it. This you can do with a fish tank air pump. The bubbles must come out right under the case you want to plate.

 

Now we are ready to go. We think the process is easy and want to start immediately. First we have to activate the electrolyte by hanging a small part of steel into it and let the current run for about 10 minutes. The color of the electrolyte will turn to a blue tone.

 

Everything is ready now and we can plate our first object.

 

 

Here, from my experience, a list of “to dos” .

Really the most important thing in plating is that you have your case carefully cleaned. Really in a perfect way. No grease or dirt. No fingerprints. Here we need the gloves and a toothbrush.

• Clean the part with hot water and household dishwashing detergent, wearing your gloves
  
• Rinse it well under hot tap water
  
• Don’t wipe it off, just shake it
  
• Spray it with brake cleaner or even put it into a glas with brake cleaner
  
• Don’t wipe it off, just shake it
  

 

 

• Put it on a steel wire, long enough +-25cm, take care to fix it well so that you can shake it without it falling off
  

The following steps will be done without touching the case, not even with gloves.

• Now we put 4 large spoons of caustic soda into a large cup and fill it then with boiling water
  

 

 

 

 

 

 

 

 

• Put into the hot liquid the case hanging on the steel wire, let it inside for +-15min, best results if you move it from time to time in the liquid
  
• Again we rinse it under hot tap water, you can take a small bowl to shake it in the hot water while the water keeps flowing from the tap
  
• We shake it to get off most of the water
  

• Now a very important part, we prepare the perfectly cleaned case to accept the plating. This is done by hanging it into a glass +-25cl filled with hydrochloric acid. We let it inside for 8-10min and keep on moving it inside the liquid
  

• Last time rinsing under hot tap water. Shaking off water residues.
  

Meanwhile the electrolyte has been heated by the fish tank heater to +30 C°, in any case more than +25 and less than +80 C°.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Over our bucket we put a plastic tube to fix the steel wire with our case to plate.

We take care that the little tube blowing fresh air into our bucket from the fish tank pump is placed exactly under the case we want to plate.

Now we fix the cathode, – pole, of our battery charger to the steel wire on which the case is hanging in the electrolyte. Just hang it a few centimeters under the surface, not near the bottom.

 

 

 

 

 

Entering the tank. Case is gold plated therefor the color.

 

 

 

The next stage will produce quite a lot of hydrogene gas, therefore no ope flame and do it in an well ventilated piece. I opened my garage door.

 

To the copper wire of our bronze anodes we fix the + pole of our battery charger.

Now we are ready to go and see small fine bubbles coming out of the case. These bubbles should not be too big. A fine mist is the best. Check this before you connect the fish tank pump which will make a lot of bubbles.

 

 

 

 

 

 

 

 

 

 

 

 

The right amount of bubbles. you have chosen the right voltage.

 

 

 

Too big bubbles mean you are plating at too high voltage, reduce voltage!

You can move a little bit the case in the liquid. When pulling it out to have a look after 1-2 minutes, you must see a fine shiny bronze plating.

 

 

 

 

 

 

Keep on at this pace. If you go too quickly you get a matte darker dull plating, here you have been going too fast. You can polish it but it won’t last as long as a slower plated case.

When you are satisfied with your result you take out the case pending on its wire.

 

 

 

 

 

Result is fine, now let it dry.

 

 

 

 

Here an example of a bad result due to a too high current during plating. This plating will not last. You will wipe off 80% when cleaning it.

 

 

 

 

 

 

Don’t touch, don’t put it down on a towel or any surface. You will have marks in your plating.

 

Rinse the case very well under tap water and hang it for an hour or two to dry completely.

After this you can touch it and take it off.

 

If the result isn’t satisfying you can do the process again. There is no risk of damage or harm to the case. When you polish the case do it very carefully not to rub off plating. Best is a jewel cleaning cloth.

 

 

Now the pleasant last stage, reassemble your “Bronzo” and enjoy it.

 

 

 

Here mine after some flame aging.

 

[fuba 0]

Very nice tutorial! Thanks!

[trailboss99 1,115]

Schweet! Tidy it up and put it in the tutorial comp mate.

[onionbag 1]

Well done.

 

I liked your home-made rheostat.

[dalboy 2]

Very interesting..getting more and more popular this kinda thing..although your end result is impressive..

 

Yes !! i like it....i feel a trip to the pet shop and hardware store coming on..

 

 

Dal..

[acharria 0]

wow... very very cool thread..

[razorblade 0]

Amazing work and great write up! You can probably do up a few bronzos for us.

[TT88 1]

fantastic tut mate!

[slvg325 0]

This is an amazing topic. Thank you

[mspangl 0]

That's AWESOME !

[Or4n6e 26]

Awesome, looks great...

[baxter 6]

[digger2 0]

Great tutorial, thank you! I love the color just after the plating.

[houndoggie 58]

I think I saw this on Breaking Bad

[moredhel 0]

Excellent tutorial.

 

Been wanting to do this for awhile.

 

Do you think this will work with titanium?

 

And what is the concentration of hcl you are using?

[beathead 0]

Great tutorial! Well done Sir!

[James. 26]

Excellent tutorial.

 

Been wanting to do this for awhile.

 

Do you think this will work with titanium?

 

And what is the concentration of hcl you are using?

 

I saw a tut for titanium bronzing and it's a much easier process. Can of coke, some foil, a jar and some batteries is essentially what's required from what I read.

 

 

Bravo JP, great read. I don't trust myself with toothpaste let alone these chemicals, but I admire the process

[JohnPilot 11]

Excellent tutorial.

 

Been wanting to do this for awhile.

 

Do you think this will work with titanium?

 

And what is the concentration of hcl you are using?

 

Thanks. Its a 20% concentration. you can buy it to clean stones and bricks outside.

Not yet tried titanium, but why not.

There are so many different alloys that you have to try.

Even for stainless steel. Some cases accept very well the bronze plating others not so well.

But the key is always cleanliness of the case to plate.

[JohnPilot 11]

Excellent tutorial.

 

Been wanting to do this for awhile.

 

Do you think this will work with titanium?

 

And what is the concentration of hcl you are using?

 

I saw a tut for titanium bronzing and it's a much easier process. Can of coke, some foil, a jar and some batteries is essentially what's required from what I read.

 

 

Bravo JP, great read. I don't trust myself with toothpaste let alone these chemicals, but I admire the process

 

Thanks, but there are many tuts on the web but to get it work you have to make your own experience.

[cwazy1 0]

where did you get your electrolyte solution?

[JohnPilot 11]

where did you get your electrolyte solution?

 

On the web, google electrolyte, bronze,

[xbb 0]

Interesting tutorial.

I'd be interested in the safety aspect of this. Is there any real danger that you could cause some sort of explosion? Sparks, hydrochloride acid fumes. Sounds a bit dicey to me.

[JohnPilot 11]

Interesting tutorial.

I'd be interested in the safety aspect of this. Is there any real danger that you could cause some sort of explosion? Sparks, hydrochloride acid fumes. Sounds a bit dicey to me.

 

Yes there is a danger of explosion. The electric current transforms a part of the water to hydrogen.

I did plating first in my closed garage but when you breathe you quickly feel a need of fresh air. To have your place is well aerated is a must.

[xbb 0]

I hope that RWG has their public liability insurance paid up in full.

 

I say that a bit tongue in cheek, but John, I think you have a bit more work to do with your tutorial before it goes out on public display.

At the very least I think you need:

A very clear warning at the beginning that there are inherent dangers in this process.

Some very specific detail of what the chemical reactions are and what dangers they pose (ie danger of explosion, danger of inhalation of fumes)

Steps to take to minimize those dangers

Probably a whole lot more

 

Don't get me wrong, I really like the idea of a tutorial on this subject, but is it something that you would want your 16 yr old kid doing in the garage of your house while out plaing a round of golf.

[Timebandit 0]

Great Tutorial

 

Greetz

Uwe