I'm glad you guys are giving this a try--I think you will be really satisfied with the simplicity of the process.
Post your results, observations, questions...
Wilf
For the home plating specialistI would have guessed DC! I think I have a large and a small one still in the attic. I used to use the small one to cut out the doors and trunks in plastic model cars by stretching a thin wire across the terminals. Time to do some digging. 66 dream, 78 cb750k, 02fz1, 09 wing
Interesting!
I found my small Lionel transformer, (from the late '50s) and sure enough it puts out a minimum of 7 volts AC and goes up to about 20 volts AV. Also found a 700+ page operating and repair manual and started digging! Didn't realize these were that complicated. I did find some rectifiers shown in some of the transformers wiring diagrams, but I think they come into play when the whistle is blown or some other function needs DC? I think some of the newer smaller transformers are actually DC all the way. I remember reading in one of the plating links that model train transformers can be used, but I probably didn't read the details. I guess it pays to put a meter on it! 66 dream, 78 cb750k, 02fz1, 09 wing
I am happy to report that Wilf is not a Taliban operative. I'm still alive an kicking in spite of running my plating system in the basement.
I decided to plate a rear wheel spacer on my CL77 as a test piece. Most of the cadmium was gone. I bead blasted it, then dropped it into phos acid until the rest of the cad was gone. Dunked it in acetone to make sure it was squeaky clean, let it dry and put it in the plater. The charger I'm using is a 2.9 volt charger from an old Skil Power screwdriver. It is rated at 0.7 watts, which translates to about 240 milliamps max output. When I put the spacer in the bath, and hooked my Fluke up to it, it showed about 300 ma. So I dug thru my junk pile and found a 1K pot and put it in series to control the current down to the 240 ma limit of the charger. My bath was brand new (and a bit novel so see Bath Mistake below), so no zinc was in solution yet. So it has taken awhile for the spacer to plate. I did pull it out after about 2 hours and gave it a buffing with a Scotchbrite pad. My brass brushes were either shot or greasy. The bath is pretty sticky stuff from all the sugar (again, see Bath Mistake below) so I would suggest scrubbing the part under a hot water faucet flow in the kitchen sink as that will get rid of the sticky bath residue (maybe not necessary if you make the bath right). By the way, the brushing process or scrubbing with a Scotchbrite is known as carding. It is similar to what you need to do between sessions when bluing carbon steel parts. So, the spacer went in the bath for another run of about an hour. I pulled it out, carded it under hot running water and it looks terrific. I'm very pleased with how it came out. But it appears that the ID did not plate as it began to flash rust. I could just grease it when I mount it, but instead I made a small cathode to fit inside the ID then submerged in a bath to plate the ID as well. It's cooking as I type this. When I pulled the spacer out of the bath, I had one of my cast iron exhaust flanges ready to go. Left it in for about a hour. It will go in for a second coat, but here is a pic after carding. Currently using power supply to plate the ID of the wheel spacer in a smaller, 1 pint tank (butter tub). I also found a good brass brush I forgot I had which is how I carded the exhaust flange. My tank is a plastic bucket that holds about a gallon. For my zinc cathodes, I cut a 36 inch strip of zinc roof strip in half lengthwise to give me 2 each, 1-1/5 inch strips. I then cut the strips to be the height of the tank sidewalls with some extra to fold over and then connect to a copper conductor. I had enough to make a surrounding wall of zinc. My understanding is electro-plating like this is line of sight. By that I mean the item being plated pulls the ions of metal straight across from the cathode. Surfaces that are perpendicular to the cathode tend not to plate while those parallel plate very well. So, by making a circular cathode, I'm assured of relatively uniform plating. I even made one very long cathode strip that runs down one side, across the bottom and then up the other side to provide a cathode for surfaces facing down in the tank. I made two more strips that were slightly too long and bent them at 90 deg to take up additional area on the bottom of the tank. Total, there are 6 vertical strips running round the outside wall of the tank and the majority of the bottom is also covered. Bath mistake In my enthusiasm to get plating this morning, I sat down at my desk and did some research on the web for this process. I found a site for school teachers that gave slightly different amounts of sugar and salts than Wilf did. Salts were a bit less by about 20%. So I used that recipe instead. However, as I was typing this up, I realized that I made a major error in my arithmatic this morning. Instead of dividing, I multiplied and the result is I have 4 more times the required amount of sugar and salt for my 3 pints of vinegar than is required. This is why my bath is more like Mrs. Butterworth's Syrup instead of just plain vinegar. Maybe Wilf can comment on what effect this will have on the plating process. My guess is it reduces the acidity and hence slows the process. Total cost to do this, is 1 strip of zinc - about $4.00 but I had to buy a whole box which was over $50. Gal of white vinegar - $2.99 4 lbs of Epsom Salts - 3.99 Sugar - Free, as I raided the wife's larder Tomorrow I will buy another gallon of vinegar to dilute my current bath down to correct properties. I suspect this will raise the acidity and perhaps speed up the plating process. Having more bath will also allow me to use a 5 gal pal as a tank so I can plate more parts at the same time. Sorry if this write-up is a bit disjointed. I started it when I started to plate the first piece and have been going from the basement to my office and adding new info and editing as I go. regards, Rob
It's funny that you say that. Besides my chemistry foot in the mouth comment recently, I was wondering if you could actually do this. The challenge would be to suspend a cathode inside the tank such that it would plate out on all the surfaces. My guess is you would be fiddling with it for hours to get it right. I think the perfect shape would be a long tent shaped piece, but you would never get that into the filler neck. Then there is the balancing act of getting is suspended off center and still not tip down and touch the tank. You would have to experiment with making the short end heavy outside of the tank, until you got it right. Not sure you'd ever be able to fish a long strip in there and be able to straigten it out to do the job.
Getting back to my first try at this, last night after posting, I fixed the bath to the correct proportion of ingredients and it had a marked improvement both on the process and the final finish. The reaction was boosted considerably with the increased acidity. The final surface was kind of an iridescent blue/gray color that when carded became a bright shiny silver. I'm on my way out to the garage to bead blast and acid etch more parts for the plating process. By the way, there is absolutely no odor associated with this, other than a mild vinegar smell. But that is only up close to the process. So you can let parts cook in the basement while you work on other things. I even left stuff plating while I went to the store. Get yourself a digital timer. It is amazing how fast the time goes by when you get involved in a side project while you are letting something plate. Yesterday I made a frame to hold a clear plastic window in front of the main window in my bead blast cabinet so the actual window does not get frosted. I had to force myself to keep checking the timer. But that was also with the wrong bath so the plating process on that first piece was dead slow. I'm telling you guys, this is a neat process and very simple once set up. I suggest you go to your local diner and see what kind of plastic containers they will give you. I know fish comes in big plastic tubs that are about 12 x 16 that I use for parts cleaning. They would work great for plating long parts like rods, brake drum stays, shafts, etc.. I think I'm about to become a plating lunatic. I'm not sure if there is a limit to how big a tank you can make. But since the bath is so inexpensive to make and can be used over and over, it is probably worth trying. Not sure if you fill a bath up with mutiple parts if they will mask each other from evenly plating due to the line of sight thing. Maybe Wilf knows. regards, Rob
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