vintage case impossible to plate

[gkmaia]

I am trying to restore a watch that is the same as the bellow one and I am struggling heaps to plate it's case with nickel.

First I thought it was something wrong with my setup, pickle, contamination, voltage/amperage, etc... but does not seem likely as other brass and stainless parts plated perfectly both in copper or Nickel or gold.

If I try to plate nickel directly it just peels, blister and streak. No matter voltage and amperage. So I made a copper base but it is not coming out clean. Has blisters, dark spots. 

It made me thing that the case must have some zinc in it. When I did my pickle with muriatic acid it bubbled crazy same as when I stripped zinc bolts. 

So... any idea of what metals were used to make these cases back in the day?

 

[HectorLooi]

I experienced something like this before. It was a trench watch. It just bubbles like crazy in the plating solutions. I eventually gave up on it, in fact I couldn't remember anything about it until I read your post.

I suspect it was made of pure zinc or some alloy of it. I'll probably powder coat it and bake it.

[gkmaia]

I could manage to get it plated but not very good. But still better than it was before. The main issue was that I had to sand way to many times the case to remove the plaiting failures. So unfortunately most of the sharpness of the case was lost... :^(

After the fist sanding I managed to get the sides levelled, seams pretty small and sharp, but it was all lost by trying to get the plating to stick. :^(

The top ring is brass so the plating was perfect. 

The back case was stainless. Did not go so well because I did not have the stainless activator.

I did one layer of copper pen plating. Then a layer of gold 24k. Then a mixed layer with 80% gold and 20%copper by mixing the solutions. Turned out on a really nice rose gold. 

I am thinking about buying the very same case and then just follow what actually worked on this one and do it perfect.