So I've done a lot more since the last time I updated. Completed my first roll of copper! Here's almost everything left: 

I've also tried a couple more materials, and did experiments like with debinding:

or washing:

Or tensile testing:

Most of the discussion for this, however, has been localized to a forum specifically for this filament. It's still experimentation but maybe not quite "hackaday". But if you're interested, you can check out more of my musings over at https://discourse.thevirtualfoundry.com/.