There is such a thing as bi-color filament (like MatterHackers Quantum PLA) which can be thought of ... it’s entirely possible to 3D print your own bi-color filament. Back when [Turbo_SunShine ...
When is a hot glue stick not a hot glue stick? When it’s PLA, of course! A glue gun that dispenses molten PLA instead of hot glue turned out to be a handy tool for joining 3D-printed objects ...