Learn me DIY cadmium plating

Father's day is coming so this is what I think I want the fam to buy me.  I want to be able to restore the yellow cad plated parts on my British cars.  What do I need to know?  What should I buy?

Looks better than I thought it would https://www.eastwood.com/eastwood-golden-cad-complete-kit.html

Won't work on bolts/nuts and I wouldn't do it the "real" way at home.

I have nickel plated, but not cadmium. 

I will try to dig up the thread when I get to the office. 

Paul_VR6 (Forum Supporter) said:

Looks better than I thought it would https://www.eastwood.com/eastwood-golden-cad-complete-kit.html

Won't work on bolts/nuts and I wouldn't do it the "real" way at home.

I assume he's talking about one of the zinc plating kits that simulates cad plating, not a spray paint.  One example: https://caswellplating.com/electroplating-anodizing/zinc-plating-kits.html  True cadmium plating is hard to find these days because of the hazards.  

Cad plating is a thing of the past due to the hazards as mentioned above. It's all yellow zinc now. Easiest and quickest to just let a plating shop re-do the parts for you. You should be able to get every piece of hardware and various widgets for a British car done for less than a tank of gas in the daily driver. 

Here is a great write up I found years ago. I bought all the stuff needed but haven't gotten around to setting things up.

https://www.forbbodiesonly.com/moparforum/threads/zinc-plating-with-yellow-chromate-conversion-how-to-achieve-that-factory-look.63715/

jgrewe, you are the man.  Exactly what I am looking for.  Can you use the same basic set up to do that black coating?  If so whats the black step?

Well, either I didn't do a thread or I can't find it. 

Nickle is pretty easy with some saltwater, a chunk of nickel, and a power supply. 

Why isn't this a tech forum article on here?

tbh the paint kits look more like cad than the zinc plating that's supposed to look like it

Watch this space. I will give you the good and bad as soon as I finish the pics and writeup

OK. This is the 3 gallon Caswell "copy cad" plating setup and everything you actually need to to do this

From left to right. Distilled water rinse bucket, behind that "pickling acid", next to that the water based degreaser, then the zinc plating bucket. the three glass jars are the chromates. Black, yellow and blue. The power supply is a cheap import thing, A battery charger does not have the current control to do this correctly. The temperature controllers handle the heaters.

Love the labeling for the fuse. Those controllers have a thermocouple and run whatever is plugged into them up to the set point desired. About 100 degrees for this process.

These dudes get plugged in and set in the buckets.

And you need to have the electrolyte solution moving for best results so there is a lab mixer under the plating bucket.

There are a lot of acids involved and if they aren't kept air tight metal around the area WILL rust. This is not a very clean process. 

You will need much more of this than you think if you will be regularly using the plating system.

OK. Prep. All the old plating, rust, grease and dirt must be removed. I took one for the GRM team and sandblasted a caliper this morning.

But that is in no way ready. If it were plated now the finish would be very dull and rough.  The next step is to get the surface finish you want by either sanding, wire brushing or in my case "Vapor blasting"

Now, put your gloves on, to protect you is secondary, they ensure you don't foul up the plate.

Now they are clean and have a surface we are happy with they go into the pickle solution. It is a green acid and I no longer remember which acid it is.

After a few minutes in there you rinse the parts in the distilled water and then into the plating tank

Suspend them in the tank with clean, bare solid copper wire. Do not use mechanics wire or stainless safety wire. A spool of copper is what you need. Attach the terminals to the power supply and dial in the needed current. How much do you need? You will be sorry you asked. There are formulas, TONS of formulas.  Start here. You know how everyone on Youtube dials up the voltage until bubbles start pouring off it? Don't do that! That will make all your hard prep work look like crap.

OK, you have stood there for 5-15 minutes depending on the item and current and you have a deposition layer that looks uniform and shiny. Turn off the power supply and rinse in the distilled water. Then place them in the chromate solution for 30-60 seconds. Rinse again and dry and you have this

A nice layer of blue tinted zinc that will last a few years. Remember that zinc is a sacrificial layer and will degrade over time as it gives off electrons stopping the ferrous metal underneath from doing so instead.

Remember when I said wear your gloves? this discoloration on the other caliper was from the part brushing my forearm while tying the wire onto it. Oils and grease will ruin things

So yes. You CAN get good results at home with a kit. It has a steep learning curve. The first 10-15 batches you will get about 25% that you are happy with. It is also slow. Is it affordable? I'd say I have invested about $1100 in that setup, You can answer that question for yourself. Is it as good as the professionals? No. The local zinc and nickel plater here recently upped their prices to $95 per batch. A batch is something like 125lbs.  It would take a very, very long time for this to pay itself back even in our busy shop. I keep this around for little things that aren't worth sending out and waiting 2 weeks for. Carb linkage, newly fabricated parts ect..

Can you mess it up. Oh very much yes. You can run the current to high and have a burnt, dull look on your part. You can plate for too long and make it rough and look like a dip galvanized nail. You can easily contaminate your electrolyte and ruin the expensive solution, you can also (as I just went through) have a well meaning person top up the electrolyte with water and add too much, diluting it to the point where it no longer works.

In reply to Trent :

Thank you very much for that!