My conclusions: The hotter the torch, the better and more consistent the water-cast cups.
Thicker gauge wire produces more rounded, well-shaped cups, while 16-gauge wire made cups with pointy bottoms.
The butane torch took longer to melt the wire, especially thicker wire, resulting in less uniform cups.
With 16-gauge wire and the butane torch, I also got cornflakes and odd shapes.
When the water warms, cups develop pointy bottoms too.
Other metals like brass, bronze, and copper did NOT form cups they mostly became balls or misshapen blobs.
I plan to experiment more with these metals, perhaps by melting the metal closer to the water or using deeper water.
The cups made from water casting have many uses. What will you make?