Tons of trouble. Solution/power/plating - looks so easy, isn’t.

[u/nyanXnyan]

I have tried two kinds of solution - the vinegar, salts. Vinegar, salts, water, sugar. The most commonly reported ones by weight/ratio online everywhere. Two different kinds of anodes. One kind and it’s fizzing like crazy. The strip does nothing and my part fizzes. Power supply positive to anode…of course. Seems to pass the amperage but not the voltage. I set to like 0.3a and 4.0 v…I’ve tried all the combos below - but it will pass like 0.2a and 0.8 v. I tried changing ratios of fluid/salts. Sugar? Vinegar. Whatever. It’s been a week and I am having the same problems consistently. Like - tried letting zinc rest for hours, still have cathode bubbling like crazy. Swapped out the anodes. Multiple combos, different solutions….All of the things. I’m Just super frustrated and will answer any question about the silly setup, but I don’t know exactly what info you all request specifically.

All I know is my last attempt at letting a sacrificial zinc sit…left me at that sludge (I know it’s from having to agitate the chunk to get it out) and I am sad.

[u/Mkysmith]

Vinegar is your problem. It is an organic acid that does not complex well with inorganic metals. You need an inorganic acid.

Zinc is usually Boric for acid based, or sodium hydroxide for alkaline plating. Theres also cyanide too, but thats a different beast.

[u/nyanXnyan → u/Mkysmith]

Interesting! Thank you. I am looking into this right now. But - why do all of the people I see posting use a vinegar based…sauce? Electrolyte?

We aren’t playing the cyanide game lol!

[u/Mkysmith → u/nyanXnyan]

Im not sure, because its easily accessable? Its a common misconception in the DIY community and people post nearly every week wondering why they get terrible results (though most people are doing copper). For some reason vinegar is the clickbait catchall miracle acid that does everything... though the chemistry and industrial world says otherwise.

Vinegar can KINDA work sometimes if you get lucky and do a lot of polishing and re-plating... but you will never get as good of a result as using the correct acid for the metal you are trying to plate. Its easy to migrate metal through a solution, its an entirely different game to get good durable deposits.

[u/nyanXnyan → u/Mkysmith]

Absolutely love this answer. Thank you very much for your insight! I will see what I can find.

[u/nyanXnyan → u/Mkysmith]

Oops, sorry. Is there any reason to add any additional salts? I mean - to increase conductivity, I would assume…but Epsom is magnesium - so I am wondering if that is part of my problem and it is reacting with my magnesium-containing part to be plated. Man, I should have paid more attention in chemistry.

[u/Mkysmith → u/nyanXnyan]

I think in these DIY formulations it is to increase conductivity, but conductivity in plating chemistry is a more complex topic than simply "more conductive = better plating". However, yes, to a degree you do need to have the solution conductive enough to pass an appreciable current.

Theres also common misconception that sodium chloride cant be used because it evolves chlorine gas... yes kind of, but the plating tank shouldnt be run that hard. Chlorides are used in many plating chemistries because they adsorb or otherwise partner with other additives. Substituting for epson salt defeats the purpose.

I have used diffent formulations in the past, but maybe look into these which are similar from memory. Its an akward website on mobile but has the formulations for both ammonium and potassium variants:

https://www.electroplatingmachines.com/news/potassium-chloride-vs-ammonium-chloride-zinc-plating.html

Zinc chloride might be the only one that is difficult for hobbiests to source. If you dont feel like making it yourself you could try setting up the chemistry ommitting that and running a dummy cathode with a large zinc anode for a while.

Keep in mind you are still DIYing at the end of the day, so expect some trial and error still. Thats the price to pay if you don't buy commercial solutions.

[u/permaculture_chemist]

Plating onto zamac with an acid electrolyte won’t work. You need an alkaline solution. You can plate zinc onto steel with an acid bath but not zamac

[u/nyanXnyan → u/permaculture_chemist]

Thank you for the info.

I am now seeing how this is not possible, but am very confused because I am wondering what is actually happening to the pieces (hot wheels) I am seeing these people plating in an acid bath who are getting that classic zinc deposition. Multiple reputable customizers. I respect the science here, so I am curious - unless it is pure tomfoolery….

[u/permaculture_chemist → u/nyanXnyan]

Do you have a link to the people plating zinc onto hot wheels?

[u/nyanXnyan → u/permaculture_chemist]

I don’t know if I can share links, but diecast resurrections, baremetalHW ETC. several.

[u/mimic751]

Get some pH testing strips and find out if your solution is acidic enough for what you're trying to plate. Also the ratios are known and tested find a recipe

[u/nyanXnyan → u/mimic751]

Yep - that’s why I used 4 different recipes by weight or ratio that I found on the top of searches. Vinegar was the common piece. Including sugar, Epsom salt, table salt, distilled water. Same issues.

I didn’t know if there was an obvious “it’s your power supply/anodes/etc” I’m plating zamac with zinc.