Does the copperfill filament conduct?  

RE:

There are conductive copper filaments around: https://all3dp.com/2/conductive-filament-brands-compared/

If you're asking about ColorFabb's copperfill, no, it isn't. ( https://support.colorfabb.com/hc/en-150/articles/360002292018-Is-your-copperFill-conductive-)

RE:

Does the copperfill filament conduct electricity?

Reliably, no.  Just occasionally you will find a conductive or resistive path through a mass of it so don't rely on it as an insulator either.

Cheerio,

RE: Does the copperfill filament conduct?

I would LOVE to have a truly conductive 3d print medium!

I've checked out every filament that claims to be conductive, and the best of them apparently will print traces that will typically have hundreds to thousands of ohms.

This may work for some low-speed logic and noncritical small signal analog, but does not come close to etched PC boards or point-to-point wiring.

I've done a few projects which use a 3d printed board with DIP and component holes, which is then stuffed and VERY carefully soldered with re-work wire.

I've also heard of some who have used 3d print filament as a resist, printed on a bare copper board using a 3d printer, and then etched in the usual caustic or acid bath, but I have never tried it myself.