By Peter Crowl
Authors Note: This was written in the 1990's. Caswell may have changed the items mentioned to make the system more user friendly by now!
I'm standing in my driveway on a crisp fall morning. In front of me is a table bearing containers full of strangely colored solutions, all with wires and electrodes hanging out of them, connected to a large battery charger. Some of the people out for their morning walks comment. I reply that I'm preparing for an upcoming chili cook-off. In fact I am doing copper and nickel plating right here at home.
After doing the article on buffing and polishing , I wanted to know if it was practical to do small part plating in my garage. The advantages would be numerous - Copper plating is used to build up corroded parts that can then be buffed to a smooth finish again. This is especially effective on trim parts and "pot metal" items. Many older machines used nickel plated fasteners which are now virtually impossible to find. If you could nickel plate at home you could strip zinc plated bolts and plate them with the correct finish. Machines have are a lot of internal parts that would be best off plated, If you paint them they could be sticky. If you do nothing they rust. A quick copper plate would be just fine. Yours is one plating shop that's guaranteed not to loose your parts. And let's not forget cost. Chrome plating is expensive and having a small chrome tank in your shop could save you a bundle.
Electroplating is a method of coating an object with a thin layer of metal. The process was discovered by Michael Faraday in the 1830's, but some ancient civilizations are thought to have had the ability to do crude plating. Archaeological digs have revealed situations in which many amphora connected by metal bars could have been a plating operation. Using vinegar and other natural acids it's quite possible.
What happens in the plating process is that positively charged ions flow through the plating solution and are deposited onto the surface of the object. The plating metal (anode) is connected to the positive side of the power source and the object (cathode) is connected to the negative. The longer the system runs, the thicker the deposit (plating). It's really very simple.
If I was going to do this, I wanted to try one of the commercially available plating sets, reasoning that this is how most people would go at it. I contacted Mike Caswell at Electroplating in Miniature and outlined what I wanted to do. Mike was kind enough to provide a one gallon version of his copper, nickel and chrome plating sets along with the instructions. I was on my way to becoming my childhood idol - Mr. Wizard!
Caswell sells plating sets for the home workshop. He offers Aluminum Anodizing sets (Imagine your headset pieces in a cool blue!), Zinc and Yellow Chromate, and even Gold plating sets. For my purpose however, I wanted his Nickel/Copper/Chrome plating kit. This set makes a 2 gallon solution for each of the 3 plating metals and sells for $295.00. I contacted Mike Caswell and explained what I wanted to do. He offered to provide a 1 gallon version of this kit for the writing of the article (Thanks Mike!).
I took him up on the offer and soon received a stack of plastic pails via UPS . The Caswell sets are shipped in these pails that are then used as the plating tanks. Inside the top pail of the stack were sealed bags containing the 3 plating solution chemicals, the metal plating anodes, litmus paper for pH testing, and instructions for each of the three metal plating procedures.
The sets require additional things that you may have or have to buy. Sulfuric acid (battery electrolyte), Hydrochloric (muriatic) acid, an aquarium heater, aquarium air pump (for circulating certain solutions) , thermometer, copper tubing, clip lead connectors, and so forth. The problem is that at no point does Caswell provide a comprehensive shopping list of these things. You have to read the directions - I recommend reading them a few times before starting - and pick out what you'll need. If you miss an item it'll mean another trip to the store. You have to be thorough.
The instructions are functional but I must comment that I think they could bear a re-write.
- So they'd be In American English. Caswell is originally a Canadian company. Some things can be confusing, like when you're advised to mask areas you don't want plated with nail varnish. I'm thinking a hardware item and they mean finger nail polish.
- To be in more of a "cookbook" format. I'm no chemist - I didn't even play one in school - but I can follow a recipe and step by step instructions. Caswell's instructions are complete but not necessarily in direct from A to Z form. It took a few readings to understand what was to be done.
- To include a list of necessary equipment and ingredients (other than supplied) to facilitate the shopping trip prior to actual work.
Having said all that, these sets do work and rather well. The only problem is that it takes a good deal of preparation and practice to become any good at it.
Plating requires a power supply, a way to keep the tanks (pails) at the right temperature, and a means of ventilation.
Power Supply: The Caswell method here is to use your 12 volt battery charger or car battery. You put light bulbs in series with the positive lead to the anodes. Mike provides a chart that advises you what size and how many bulbs to use for the size piece you're doing. This system works, but if you're going to be serious about it, you'd want to make or buy a real variable power supply.
Temperature Control: Caswell suggests the use of aquarium heaters to maintain temperature. I found that taking a plating tank from 50 or 60 degrees to the necessary 100 to 115 degrees took forever using this type of heater. It was suggested to me that I use a sort of double boiler method - placing the tank in a pan of water over a burner. Since I didn't want caustic solutions simmering on my stove in the kitchen I did this using a Coleman propane camp stove.
Ventilation: These tanks can put off some serious fumes, especially if you're doing Chrome. If you're in a closed room, you must have a vent hood that vents outside. I choose to do the work outside.
The Caswell sets include, besides the plating chemicals, a caustic parts cleaner / degreaser solution base and instructions on making a plating stripper / etching (pickling) solution.
Armed with all these tanks and supplies, you can actually begin plating. You have to play with it as I mentioned above. Taking notes as you go to determine the best power supply / temperature / time combinations.
What you do is take your buffed part to the cleaner tank (140 to 160 degrees) for 2 to 10 minutes, rinse the part in hot, then cold water. Next to the pickling tank for 30 seconds, rinse the part in hot, then cold, water. then to the Nickel tank. If you're going on to Chrome, you have to heat and maintain the Chrome tank at between 110 and 115 degrees (f) accurately. It sounds easy but you have 3 or 4 tanks to keep at temperature, at each step you connect the part to different lines and cathode bars on and on.
I got to feel like Lucy Ricardo trying to keep up with the conveyor line. The fact is if you're doing just a few parts (and these sets aren't up to doing large pieces like wheels or body panels) for a scooter restoration I don't think it's worth the grief. And doing a few pieces now and then, you won't develop the skills you need to do good work. If you could lay just copper over a part and buff it out it's be easy. Problem is on a steel part you have to go through the nickel stage first so you have to set up all the tanks.
If you can substantiate keeping these tanks set up in one place with a power supply that serves all of the tanks at the change of a switch, it would be alright. To drag the whole thing out, set it up, warm all the tanks, connect and re-connect the power supply and bulbs is a full time job. I think you'll find a plater would do a polished part for a reasonable price and that would be a far better way to go.
If you want to do plating as a sub-hobby or if you have a lot of things to do that will substantiate the $295 by all means consider the Caswell sets. They're a great way to get into it.
Sources:Plating sets and supplies:
Caswell Electro Plating in Miniature
4336 Rte 31
Palmyra, NY 14522
315 597-5140Chemicals, power supplies, books:
Star Route Box 165
Topton, NC 28781
You're working with some very serious caustics.
- You'll need Chemical resistant gloves
- Eye protection - goggles
- Full clothing - a rubber apron is good
- Maximum Ventilation. Work outside.
- Follow all the safety rules that come with the Caswell sets.