Hi, long story short:
I found this on youtube: https://www.youtube.com/watch?v=S-kn_HO2tKM&hd=1
Then I found this galvanisation set in Conrad: https://www.conrad.de/ce/de/product/530506/
With this set you can electroplate copper (for example) with gold, silver, zinc (not tin!) or nickel. It is pretty expensive, but I didn't find nothing special in this "tool" - it is just battery holder with simple electrode and sponge! So, I wonder can I DIY such a "pen" like in the video above, maybe with ordinary plastic felt pen - just to connect some wire to felt-top, wet it with zinc-electrolyte (or even fill felt pen "filter" with a little of it!) and continue as in youtube video!?
There is also possibility to use nickel-electrolyte, but my concern is, since the nickel is ferromagnetic metal, maybe it could cause increased eddy currents or something like that?
In attachment: user manual for zinc-electrolyte - it is in German, if you need some help - I'm here!
Why would you want to plate PCB with zinc? Thin zinc will not likely do much to protect copper underlay. It will likely desolve into any solder joint where in local concentration may weaken solder joint similar to heavy gold plating (see gold embrittlement).
Ok, no zinc. But what about nickel? I would like to see my PCB nice "silver-glowing" for both: protection and strengthening tracks and pads. Silver plating?
Silver is good for conductivity but bad for electro-migration. Electroless nickel is the most common and easiest application. Comes in solution you just soak the board in for a few minutes. You can also do this with gold solution but much more expensive.
That's interesting! Something like MG Chemicals "Liquid Tin". But it is very hard to find this kind of stuff in Europe! So, the only option remaining is hot-air tinning with Rosol-3 or so - Sn-soldering paste (for use in plumbing)...