Material that doesn't melt at 800 deg F, but can be dissolved? I'm a sculptor and I have a chemistry/plastic question. I thought here would be a good place to ask.
I'm looking for a substance (probably a plastic) that has these characteristics:


Doesn't melt at the annealing temperature of Copper (doesn't melt at 700 degrees Fahrenheit)
Can be dissolved/made non-solid/melted by a process that will not affect copper (a specific acid?)
Is available in a wire form
Is relatively flexible


I want to wind long coils of tiny copper wire around a flexible core (the plastic I'm looking for), form that coil into complex shapes, then get rid of the core so as to be left only with the copper wire showing

I understand these requirements are perhaps impossible to meet...Just wondering if someone with good knowledge of plastics maybe has an idea.
Aluminium and Magnesium 
react vigorously with mineral acids. 
A lot of heat is evolved. 
Try iron/steel wire, which is cheaper and 
available in any diameter. 
Georg