1/20/2006 Rev. 3

 

A few thoughts about plating and your Model A.

Recently I spent a lot of money to have a bunch of rare parts ruined by a reputable plater. This was after I wrote up 10 pages of instructions with pictures of what I need done and what had to fit where. Keep in mind I am not an expert on plating. I have a functional understanding of the processes. What I am writing about the plating processes may have some slight errors, but they do not affect the overall meaning of my thoughts.

The plating shops are mostly set up to do decorative plating. This means that they really want to make your parts look pretty, smooth and shiny. This does not mean they are not thinking about making your parts look original or work like original.

You have to understand a little about plating to understand what the plating shop has to do to your parts. Plating is about layering compatible layers of metal to get to the final coating you need. Different base metals need to be handled differently. For example, pot metal is made out of materials that some plating solutions will dissolve before any plating is laid on the part. So they must first play some tricks to put a layer of metal on that will seal the pot metal then move onto the next layer. For steel you must first put on a layer of copper because the nickel does not easily plate directly to steel. Decorative chrome plating should be thought of as a decorative clear coat as it only adds a blue tint to what is under it. That is why there is always a nickel plate before a chrome plate. There are also different types of plating solutions such as an acid copper plate which is better for doing the direct plating to steel. There is a cyanide copper solution which is better for putting a thick layer on when doing pit filling. Each layer of material will show the defects or details from the layer before and each layer needs to be polished out before the next layer is put on or you will not get a shiny next layer. This is just like how you make the surface of a car ready for paint.

When you here the hype about doing triple chrome plating that means the shop is doing the plating correctly, for steel. He is putting down the copper base, then a nickel plate and finishing it with chrome. If you send him a copper or a brass part he may just have to lay down some nickel and then chrome.

There are two types of nickel plating (well there are thousands of them, but they generally fall into two kinds). There is the original process commonly called the Watts process which is a dull nickel. I am not sure of all the proper names of the nickel processes so I will use the term Watts and dull nickel interchangeably as they are close enough for what I have to say. This is just a mixture of nickel sulfate and nickel chloride. You buff the copper plated (assuming this is a steel part) part and then plate it with the nickel. After you plate with a Watts solution you then have to buff it out again because it comes out with a dull surface kind of like the dull side of aluminum foil. Then there is the bright nickel plate solutions. They are based on the mix of nickel sulfate and nickel chloride, but they add some chemicals to make it bright. With this solution a properly prepared part will come out of the solution bright and shiny ready for the next step without buffing, just like the shiny side of the aluminum foil. This is a great time saver for the plating shop as all they have to do is wash the part and put it right into the chrome bath. The bright nickel plate has a draw back. The extra chemicals they put in also tend to cause the nickel plate to tarnish much faster, requiring buffing more often. This is one reason why some guys have all their model A parts chrome plated instead of just stopping at a nickel plate. The chrome will prevent the tarnishing, but the chrome also significantly changes the color and look of the parts. Back to the nickel processes. This is an on going learning process and I have learned some more details that alters what I say some- but not completely. I will leave it as above for understanding purposes( the idea is sort of correct, but terminology and processes are not quite as I say- maybe). In the future I anticipate some changes as I confirm some recently learned information (1/20/20006). Just bear in mind this is a simplified account of what happens.

Some evidence of Ford using a dull nickel you just need to know what you are looking at on a print. If you look at the Ford prints for the bumpers you will find the required process for plating. They specify, copper plate, buff, nickel plate, buff, chrome. Notice the word buff between nickel and chrome. Bright nickel plate is used because it eliminates the costly buffing step before the chrome tank. Ford required a buffing between nickel and chrome so that would mean they had to do a buffing which is consistent with the use of a dull nickel plate.

The only process Ford used on the Model A’s was a Watt's or dull nickel process. This is important to those trying to get the proper look on their A. The two big items where this will make a dramatic difference is on the bumpers and the cabriolet landau irons (there may be more but I am not aware of them yet). The bumpers and the landau irons have places on their back sides that were not buffed. So the Watts process would have left a dull nickel plating on those surfaces so when they are plated with chrome they will look dull. As I found out on the back of my landau irons the little depression that should be a very dull gray, bright nickel comes out real shiny and looks wrong. Here is where you need to get out your piece of aluminum foil. Wrinkle it up and then flatten it out. The dull side is more like what these areas should look like, but the shiny side is what you get. It just does not look right.

Of course finding a plater that has a Watts solution and is not afraid to use it can be another challenge. One plater I was told was real good at doing Model A parts does not even have a Watts tank and when I asked if he had one he made was clear that he had no interest in doing business with me. Another plater has the tank, but admitted he had problems with doing chrome over Watts. I did find a plater in Philadelphia, Frankford Plating, that has 3 types of nickel tanks. This plater has bright nickel, dull nickel, and a nickel that is used on cars older then the Model A. I visited this shop and what I saw looked good and he told me he strives for restoring the part, not just making it look pretty. I have not had any work done by him so I can not comment any more. I will be using him in the future.

The problem of getting you part restored verses getting them made pretty is a tough one. Some people have gone through the trouble of working with a local plater. They have the plater do all the plating and they do all the finish work. Working on the parts is very much like leveling a panel before painting. The shops all tend to use power tools to grind the parts smooth and then fill with copper and work the parts quickly with power tools. This is why many parts are wavy and loose gross amounts of details. Also they will tend to take all the cast parts and just sand and buff all the details out. But most of the Ford parts were not carefully sanded and buffed out. In fact if the area was not seen it was left a rough casting. This a true on some of the castings used on the cabriolet. But when I got the parts back they were all sanded smooth and extra nice on areas that are never seen when installed. The parts were also no longer functional as the hinge parts did not fit together anymore. I had some brass parts plated also. Brass is pretty easy since they are not rusty and they really do not need much if any copper build. All they really need to do is strip the old plate and clean the base metal, fix the minor problems and plate them. The brass parts were no where near the correct original shape.

So when you take parts to the platers you have to be clear that you need the parts restored and you wish to maintain the original details. Request and be willing to pay for hand working of the parts. You really want the long square parts hand worked. If you have any pitting be clear that you want the pits filled and not ground out. It is common to just grind the part below the pits then plate it with a lot of copper and sort of rework it to the original shape. My top irons were a uniform 3/16 thick when I sent them out. They came back 1/8” at the edges and substantially thinner in the middle and they looked like a sword blade. I hate to think what would have happened if they were badly pitted. Of course I was specific that I wanted this part to have square edges and that instruction was ignored. I also had problems with the parts being ground too much so the head of the counter sunk screws were now above the surface of the part. The hinge point of my top irons, they were plated together like they were originally, was not properly sanded to clear the build up of copper so they did not bend easily. This is a problem because the top is not made to handle a real tight bend on the top irons.

If you wanted to save some money you can talk to your plater about acceptable ways to fill in pits. You could sand blast the part real good and fill the areas with a 95% silver solder and hand work it close to the original shape before you send it to the platers. You must ask the plater what the will accept. Keep in mind the buffing process may heat up the base metal enough to melt some types of solder.

One other area that I can not give good advice on yet. The emergency brake lever and shifter have a textured surface. I have not learned enough to tell you what to look out for.

Well I hope I have given you a few ideas on what to expect with plating. I am sorry I can not tell you a place that will get your job done right. It is expensive and you are at the mercy of the plating gods.

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