For the home plating specialist

[Wilf]

The shadow effect will not be minimized by soaking the zinc for a longer time. Plating is 'line-of-sight' so all you can do is have zinc anodes spaced around your bucket and along the bottom, and then turn your part a couple of times.

I believe Snakeoil has a post in this thread describing his efforts and plating rusty chrome.

Wilf

[conbs]

You may want to try soaking rusty parts in some of that liquid rust dissolver. Eastwood sells Rust Dissolver, but there are other brands and are likely cheaper. Harbor Freight even sells one called Evapo Rust and it seems to work pretty well. It not only takes all of the rust off, but brightens up the zinc plating to like-new. I would expect getting that gunk off of your parts would make for a much better plating job.

I read that gently stirring your plating solution helps reduce the shadow effect. When the solution is still, the current would tend to take the shortest distance - a straight line. If I understand the theory correctly, if you get the ions into solution (letting the zinc dissolve), when the solution is stirred, the closest ions will plate onto your part. That is, electricity knows no direction, it just finds the least resistance. If I am misunderstanding that, someone please straighten me out.

I got my plating outfit assembled, but something is not right. It plated, but not very well and I had a hard time getting it to plate at all without creating a lot of bubbles. I haven't had time to get that problem straightened out yet, so I haven't had an opportunity to try the stirring action. If you do try it, please report back what happens.

[Snakeoil]

I suspect that your solution is brand new and does not have sufficient zinc ions dissolved. Let it sit overnight in the plating bucket and tomorrow will be better. You should read the entire thread because this stuff is all discussed.

Stirring makes sense. I made a circular anode so I get really nice, uniform plating. I had a bottom anode on my first set up and left it out on the second set up and saw no difference.

Save all your scrap zinc from making the set up or when you replace your anodes. Cut it into pieces and drop into your bath when it is new or stored in a jug. It will preload the bath with zinc.

regards,
Rob

[conbs]

Snake, I originally put a couple of big pieces of zinc in my solution to preload it with ions. Over a couple of weeks they completely dissolved. I did add a little more vinegar to the solution right before I started plating and perhaps diluted it too much. I have added some more zinc and it is dissolving now.

I will go back and read the thread again per your suggestion. I obviously did something wrong and maybe I will figure it out. Thanks so much for your help.

[Snakeoil]

I have no idea how exact the solution mix has to be to work properly. But the epsom salts are what makes the solution an electrolyte so when you added vinegar, you reduced the electrolytic properties of the solution.

My suggestion to anyone trying something for the first time is do everything exactly as the instructions state. Don't take short cuts or "improve" on the process until you have been able to duplicate the results using the standard process. This way, if things do not work it makes it easier to figure out why. Start adding variables of your own and it makes solving a problem that much more difficult.

If you are using meters, you can make sure you have good connectivity on your system by watching the meter readings change as you connect parts. Without meters, you won't know if you have a bad connection. The sugar in the electrolyte makes spashes onto the hanger wire (cathode) turn into insulation and you think things are fine, but in reality nothing is happening. I've run into this with mutiple small parts hanging from small stainless hook made from saftey wire. They don't have much weigh out of the solution and hence will often not make contact. When the batch is done, I find one part that never plated. This is something else for you to check. If you poured your electroyte in over that hanger wire, chances are it is now well insulated with a tasty sugar coating.

This problem can also show up in how you connect your power source to the set up. I use small alligator clips and because the solution does drip on various bits as you remove parts, I've had it coat the connection points as well. I find I have to wire brush the connection points and the hanger wire at the start of every plating session. Solution sitting on anything over night leaves a candy coating the next day. And you really will not see it. Same goes for your hangers. I drop my hangers into a container of warm water while I'm plating parts to dissolve any sugar that's precipitated out from the last trip thru the bath. I even store them in a plastic container of clean water so they are ready to go next time around.

regards,
Rob

[conbs]

I misspoke. What I added was more of the vinegar/epsom salt/sugar solution that I had premixed, so the electrolyte solution should have been correct, sans the concentration of ions from the original solution.

I may have some kind of connection issue. I have both amp and volt meters. At first the reading were very low and after watching for a while it did not appear much plating was happening. When I turned the rheostat up, nothing would happenn until I reached a certain point and then the amp meter would jump and bubbles would appear instantly. I just did not have enough time to chase everything down, but I didn't expect a connection issue because of the bubbles. It would seem to me you could not pump too much power (and cause bubbles) with a bad connection.

Could it be I did not prep the bolts properly? I did not put them in a pickle, but cleaned them with acetone before putting them in the set up. I guess I need to get out in the garage and try some different things, but I didn't think the above were my issues, so I am trying to find the best place to start. Thanks again for your help, Rob.

[brewsky]

Update to an attempted repair of rusted chrome throttle shaft:

This shaft is from a bank of CB550 carbs. The exposed area between the carb bodies was rusted pretty bad in one area and slightly in another.

Wire brushed the bad areas, dipped in Works toilet cleaner for a couple minutes, rinsed, dried and immediately immersed in plating solution.

This is the same batch mixed up last April that I have used several times since. Only took a few minutes with the 2 C batteries.

The plating brushes off the chromed areas easily with a brass brush, but sticks to the pitted areas.

Not perfect, but way better than a rusted area, and hopefully prevents any further rusting.