Electroplating at Home

[Davy]

Been a while since I posted something on here. I have many projects going on at the moment and I thought the community would find this interesting. Especially you folks restoring classic cars.

I've been restoring one of my dream cars (more about that in a separate threads I guess), and due to the pandemic it has been really difficult to find timely electroplating services. The wait times range from 3 to 6 months just to submit plating jobs. So I decided to take matters into my own hands after seeing a couple of friends doing it with great success.

Unlike my usual DIY posts, this is not a step by step "how to", but sharing my experience and a few gotchas when electroplating at home. 

I'll mainly be talking about Zinc plating, but most of what I've shared here is transferrable to Copper, Nickel and Gold plating as well.

Before I get started it must be said that plating involves dealing with hazardous chemicals and substances. So protective gear is a must, and ensuring that you work in a well ventilated area and keep children and pets away from your plating station.

I purchased a 10L Zinc plating kit from a local website which includes pretty much everything you need to get started including the power supply and an extremely detailed plating manual. 

 

The next step is to set up the plating station. One of the challenges for me was to find a work surface large enough to be able to accommodate everything. I already had a couple of foldable tables and I set the station up on those. My garage is still a work in progress - so excuse the mess.  

I got square 20L containers - a lot of them! And about 50L of distilled water cans (5L x 10). You should absolutely not use tap water for this as it contains Chlorine and other impurities that would cause poor plating and interfere with the electrolysis as well.

So once the station was setup, it looked like this:

 

The process of electrolysis can be broken down into several steps:

1. Cleaning and degreasing the metal surface: The metal surface is cleaned and degreased to remove any dirt, oil, or other contaminants that may interfere with the plating process. 
2. Immersing the metal surface in the zinc plating solution: The cleaned metal surface is immersed in a solution containing zinc ions. The solution is usually an acidic solution of Zinc Sulphate or Zinc Chloride (my kit contains a Zinc Chloride powder to be mixed with distilled water to make the electrolyte).
3. Applying an electric current: An electric current is applied to the zinc plating solution, causing the zinc ions to be attracted to the cathode (the metal surface being plated). The zinc ions deposit onto the surface of the cathode, forming a thin layer of zinc.
4. Removing the plated parts: Once the plating process is complete, the parts are removed from the solution and rinsed to remove any excess zinc ions.

In my photo above the containers towards the left of the Zinc Plating bath are cleaning and prep solutions. I have a strong Hydrochloric Acid solution where corroded or previously electroplated items can be placed (while monitoring) for a while until rust and plating is removed. 

What I do is use a wire wheel and then a paint stripper pad to polish the parts as best as I can so that the surface is nice and clean. I tried sand blasting some of the parts, but I was not a fan of the grainy texture which results in a dull finish. Cleaning it with a wire wheel and paint stripper disc gives any metal surface a nice shiny and clean finish which is what you want. It goes in the HCL acid for about 30 minutes after that. 

Here's a photo of a bolt before and after cleaning with a wire wheel and paint stripper. The bolt on the right used to look like the bolt on the left. It actually looks like it's already Zinc plated!  Preparation is definitely key!

 

After the HCL acid dip, the part is taken out and rinsed in a distilled water bath for a few seconds. Next, it goes into a detergent bath which is sort of a soapy water solution. A toothbrush is used to brush every nook and cranny of the part and then it goes into another distilled water rinse. Then it goes into a second distilled water rinse as the first rinse could contain impurities from the detergent.

From this point onwards, you cannot touch the plating parts. In fact, you shouldn't touch them with bare hands after the HCL bath. Wear gloves and even with gloves, handle the part with extreme care and ensure water does not bead on the part. Use copper wire and secure the part so that it can be hung in the electrolyte.

Next comes the most interesting part - the actual plating. Lay the aluminium bars on the top of the bath and connect to the power supply as covered in setting up your bath.

Check the Zinc Plating chemical temperature. It should be operated at a temperature of 25C - 30C to achieve the best results. I used a cheap aquarium heater set at 28C to ensure that the bath is always within the optimum temperature range. I also use a small aquarium pump to ensure the electrolyte is moving around - this ensures an even plating. Especially if the part is odd shaped. 

Connect the power supply and wire up the leads. The zinc anodes are hung on the positive line and the plating work is hung on the cathode. 

How long you leave them in is up to you. Recommend between 45 and 60 mins. After you place them parts, ensure all connections are secure and switch the power supply on. As a rule, approximately 1A of current is needed for 160cm² of plating surface. You should see a fine fizzing from the plating parts after a few minutes. Excessive fizzing is bad and it means you are running too much current. 

Here I have a few bolts and washers being plated. 

When you remove zinc items from the bath, it goes into another distilled water rinse. You should absolutely not touch the parts with your hands, but just hold them via the Copper wire used to hang them.

Looking good so far!  

 

Next it goes to an Activator (called METEX IT). This brightens up the hardware and preps them for the gold passivate. Move the parts around in METEX IT for 30 seconds. Afterwards, it goes again into a (new) distilled water rinse. 

The Gold Passivate the is the tub with the orange liquid (looks like Fanta lol) on the right most corner of the bench. The parts go in there for about 20 second (5 to 30 seconds recommended - the longer you have it there, the stronger the gold colour). Move it around gently.
 

Finally it goes to another (new) distilled water rinse. But this time you only dip the parts once and take them out.

Then hang them to dry and admire your work!

Here's more parts I have plated so far (mainly suspension nuts and bolts) and the bracket kinda thing you see is a trunk lock mechanism.

 

I'm extremely happy with how the parts turned up. I must admit that the first couple of tries were unsuccessful and I had to plate again. But practice makes perfect. There are a few variables that can go wrong, if you stick to it, you can't go wrong.

 

That trunk lock used to look like this before cleaning and plating:

Hope you enjoyed reading that as much as I did writing it up! Cheers!

Edited January 16, 2023 by Davy

[iRage]

Wow !

 

[inesh Gunasekara]

Thanks for explain detailed.

also can i know where can i purchase this kit ? i also wanted to try