How To Make A Conductive Plastic Filament For 3D Printing Electronics

This is based on the paper A simple, low-cost conductive composite material for 3D printing of electronic sensors by leigh et al if you want to look it up. Warning – this used a highly volatile solvent and you really need to do it in a fume cupboard, very well ventilated space – or outside – and resist the temptation to peer in while having a cigarette! – it uses
7g polycaprolactone,
1.125g graphite,
100mL dichloromethane

though you can use acetone or ethyl acetate as the solvent and conductive carbon black as the additive