Well, I know it's hard 🤣
I would imagine mild steel with liquid enamel base would be most logical (given the required thinness). You can then either paint or put silver foil or something on top.
For context, a "regular" watch dial is around 0.4mm (0.016in, give or take, or about gauge 28). Note that this is the entire thickness, not just the metal. Also, for context, flat enamel usually has something like gauge 18 or 20 copper base with about that much more thickness in enamel/glass. More context, "standard" cloisonne wires are around 0.04in height (yes, that's more than double the thickness of the entire watch dial).
A "thick" watch dial is around 0.8mm, or a bit shorter than a standard cloisonne wire. Again, this is the entire thing.
I tried to do some modding by brushable liquid enamel on gauge 30 (malleable) copper. It... didn't come out well. Even with even counter from the beginning (so I brushed on both sides, same thickness), the copper is so thin that it warped, unevenly. It looked so bad that I didn't bother with trying to put it into a real watch.
My current try is 1008 steel with liquid enamel. My result so far is that the steel holds, but the enamel was burnt out around the edge. I am trying again with slightly thicker (and different, more iron-oriented, enamel) application. I am also trying to dome the copper to see if it helps.
Another option is to take the pre-enameled board by Thompson Enamel and cut out (with a jeweler saw?) your base, then paint or add foil on it. I have zero skill with jeweler saw, and my attempt to get some water-jet cutting has been unsuccessful, so... But you might have more luck than me.
Cześć
Cyferblaty robię na krążku srebrnym. Grubość 0,7 mm.
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