You can use any acceptable, thin gauge uncoated metal wire as a cathode suspension wire (copper, titanium and brass are good to use). Paper clips are generally made of steel, which will destroy your electroforming solution! Do NOT use it to suspend inside your tank! Steel, aluminum, iron, and some other alloys should not be used.Provided in the electroforming starter kits is a spool of 26 gauge uncoated bare copper wire.